**Steps to reproduce:**
* install `l10n_lu_reports`.
* Create a company in Luxembourg with a `company_registry` number set.
* Link this company to an accounting firm that is a natural person (independent accountant) with no business registration number — i.e. `l10n_lu_agent_rcs_number` is left empty on the agent partner.
* Go to the tax report and generate the XML declaration.

**Observed behavior:**
* The `<Agent><RCSNbr>` field in the generated XML contains the company's own `company_registry` value instead of `NE`.
* The file is rejected by the Luxembourg tax administration.

**Cause:**
* In `l10n_lu_generate_xml.py`, the `agent_rcs_number` template value was built with a plain `or` chain: `agent.l10n_lu_agent_rcs_number or company.company_registry or "NE"`
* When an agent is set but has no RCS number (natural person), the fallback incorrectly continued to `company.company_registry` instead of stopping at `"NE"`.

**Fix:**
* Use a conditional expression so that `company.company_registry` is only used as a fallback when **no agent is linked** to the company: `(agent.l10n_lu_agent_rcs_number if agent else company.company_registry) or "NE"`

opw-6044689

Forward-Port-Of: odoo/enterprise#112968

### Issue:
When the company `tax_periodicity` is set to quarterly, the generated SII invoice JSON still uses the monthly period format

According to the documentation, the options for Periodo include distinction between monthly and trimester (p224 - 225):
https://sede.agenciatributaria.gob.es/static_files/Sede/Procedimiento_ayuda/G417/FicherosSuministros/V_1_1/SII-Descripcion-ServicioWeb-v1-1_es_es.pdf

### Cause:
The invoice JSON generation does not consider the company's `tax_periodicity`

This logic was probably omitted because `account_reports` may not be installed
However, when the periodicity is configured, the generated SII document should reflect it correctly

### Steps to reproduce:
- Install `l10n_es_edi_sii` and `account_reports`
- In Settings, set `Tax Periodicity` to `Quarterly`
- In Settings, set `Tax Agency for SII` to `Agencia Tributaria Española`
- Change ES Company vat number to `ESA12345674`
- Create an invoice (Date: 01/05/2026, Customer: ES Company)
- Open the generated JSON document
- Check the Periodo value, it should be 2T in May

opw-6050587

Forward-Port-Of: odoo/odoo#267708
Forward-Port-Of: odoo/odoo#264063

This commit will affect all certification modules for the POS (pos_blackbox_be, l10n_se_pos, l10n_de_pos_res_cert)

Inside the base `handleDecreaseLine` we match all the lines which have the same product_id and compute the new quantity based on those. At the end we create a new line with the decreased quantity. This method is called when `disallowLineQuantityChange()` returns `false`, so when either of `pos_blackbox_be`, `l10n_se_pos` or `l10_de_pos_res_cert` are installed.

The problem is that different combos will still have the same product_id and total_excluded_currency, so the
`current_saved_quantity` adds the other unrelated combos together and tries to remove from the total of all the combos with the same parent.

This commit will keep the decrease line for an order in the uiState. So instead of iterating over all the lines in the order and matching lines which have the same product_id we always keep track of the original line and the matching decrease line for that line.

Task-[6173236](https://www.odoo.com/odoo/project/1737/tasks/6173236)
---
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Forward-Port-Of: odoo/odoo#262744

Issue
Upon initialization of the pos a PaymentInterface is constructed for every pos_payment_method (even archived pos payment methods ?!). [As we allow only one WebSocket subscription per channel](https://github.com/odoo/odoo/blob/4e1c89890c5fd54a79dcf5bf20268e51d8fe6e69/addons/point_of_sale/static/src/app/utils/payment/payment_interface.js#L100) for the PaymentInterface, all webhook responses will be linked to only one PaymentInterface. Meaning that when you have two Mercado Pago pos_payment_method terminals configured, only the first pos_payment_method (id=1) will be subscribed to the WebSocket and all the webhook responses from the second pos_payment_method terminal (id=2) will arrive to the PayementInterface of the first pos_payment_method (id=1). Where payload.payment_method_id (id=2) != this.payment_method_id.id (id=1).

Solution
- Only iterate and create a PaymentInterface for compatible pos_payment_methods which are active
- Check if the webhook response is linked to the PendingPaymentLine

opw-6069455

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Forward-Port-Of: odoo/odoo#262184

Issue
-----
Labels generated with DHL do not respect the template (dimensions) set on the
delivery method.

Steps to reproduce
-----
- Set up DHL
	- set label template as 6X4_A4_PDF
- Create a delivery using the method
- Validate the delivery

> The generated label is in 8x4 inch format instead of 6x4 full page

Explanation
-----
All info below was found in DHL's API doc from the following YAML file

https://developer.dhl.com/sites/default/files/2026-05/dpdhl-express-api-3.3.0.yaml

There are 2 issues with the current implementation regarding the label format.

1. The formats defined on the model (the `ProviderDHL` `delivery.carrier`) do not match the ones of the API. From the API, the accepted values are the following:

- ECOM26_84_A4_001
- ECOM26_84_001
- ECOM_TC_A4
- ECOM26_A6_002
- ECOM26_84CI_001
- ECOM26_84CI_002
- ECOM26_84CI_003
- ECOM_A4_RU_002
- ECOM26_84_LBBX_001
- ECOM26_64_LBBX_001

(values taken from the excerpt below)

```
templateName:
    description: >-
      Please enter DHL Express document template name.
      <BR>                Sample Transport label
      templates:<BR>                ECOM26_84_A4_001
      <BR>                ECOM26_84_001 - default<BR>
      ECOM_TC_A4<BR>                ECOM26_A6_002<BR>
      ECOM26_84CI_001<BR>                ECOM26_84CI_002 - supported
      single customer barcode<BR>                ECOM26_84CI_003 -
      to be used if customer barcodes are used<BR>
      ECOM_A4_RU_002<BR>
      ECOM26_84_LBBX_001 - supported for loose BBX shipment<BR>
      ECOM26_64_LBBX_001 - supported for loose BBX shipment<BR>
      [...]
    type: string
    maxLength: 25
    example: ECOM26_84_001
```

[...]: additional info unrelated to labels (useful only for other `typeCode` values)

Since `ProviderDHL` is a model, the `dhl_label_template` selection values cannot be changed and must thus be mapped to the corresponding API values.

- 8X4_A4_PDF => ECOM26_84_A4_001
- 8X4_thermal => ECOM26_84_001
- 8X4_A4_TC_PDF => ECOM_TC_A4
- 6X4_thermal => ECOM26_A6_002
- 6X4_A4_PDF => ECOM26_A6_002
- 8X4_CI_PDF => ECOM26_84CI_001
- 8X4_CI_thermal => ECOM26_84CI_001
- 8X4_RU_A4_PDF => ECOM_A4_RU_002
- 6X4_PDF => ECOM26_A6_002
- 8X4_PDF => ECOM26_84_001

Couple notes about this matching:
- There is no 6x4 in the API, so A6 is used instead (A6 is 105x148mm, 4x6 is   101.6x152.4mm so not a perfect match but the best option still)
- ECOM26_84_001 and ECOM26_A6_002 are used as default values for the respective   formats when there is no exact match possible (eg 6x4 only has one option in the API, the default one)
- "A4" is being ignored, because of point 2

2. There is a specific field to force the label to be in A4 format (according to the API, see excerpt below)

```
fitLabelsToA4:
  description: >-
    To print respective Transport Label and Waybill document into
    A4 margin PDF.<BR>                Note:
    ECOM26_A6_002,ECOM26_84CI_001,ECOM26_84CI_002,ARCH_6X4,ARCH_8X4
    template. <BR>                This option is applicable only
    for PDF encodingFormat selection.<BR>                false:
    Transport Label and Waybill document will use default margin
    settings (default behavior) <BR>                true:
    Transport Label and Waybill document will print into A4 margin
    PDF
  type: boolean
  example: false
```

-----
Ticket:
opw-6148713

Forward-Port-Of: odoo/enterprise#117281

Steps to reproduce:
- Activate Anglo-Saxon accounting
- Create a product with track inventory and an automated inventory valuation product category
- Define MTO on the product
- Add this product to an Analytic Distribution Model (i.e. Legal)

- Create a SO for this product
- Create and confirm the PO related to it, the Analytic account is set on the PO.
- Confirm the reception of the product
- This creates a Stock valuation layer with the Analytic account
- Confirm the SO
- Confirm the delivery of the product
- This creates a Stock valuation layer with the Analytic account too
- Create the Invoice

Issue:
Missing analytic account on the 110300 Stock Interim (Delivered) creating unabalanced analytic accounting

Other:
test_report_invoice_items_anglo_saxon_automatic_valuation
introduced in this PR https://github.com/odoo/odoo/pull/205777
checks that in a project's analytic report, the values based
on cogs lines are displayed in the cost section.
With this fix, both cogs lines will have an analytic account
so their impact on the project analytic report will even out.
This made the test fail.
To keep the benefit of this test, we simulate that the user manually
removes the analytic account on some of the cogs lines
(those targetting stock interim received).
The test was removed by https://github.com/odoo/odoo/pull/236971
from 19.2 onward


opw-6060567

Forward-Port-Of: odoo/odoo#266617
Forward-Port-Of: odoo/odoo#261798

Applying stock quants validation was performing poorly due to multiple bottlenecks in `Picking._check_entire_pack` and `StockMoveLine._apply_putaway_strategy`:

* **Redundant updates** were performed on `location_dest_id` in the move lines and the package levels (which internally update all related move lines too), even when the location remained unchanged.
* The main loop inside `_check_entire_pack` was **O(N^2)** time relative to the number of move lines due to internal filtering logic.
* **Cache misses** triggered unnecessary SQL queries when retrieving `move_line_ids` from `package levels`, while they are already cached via the pickings and can be grouped by `package_level`.

---

### Benchmark
Benchmark conducted on a customer database with **400k** `stock_move_line` records within **800** `pickings`, testing performance of the action `StockQuant.action_validate` with different sizes of move lines. Each test was run multiple times and shown is the average mean, all with negligible variance.

| Metric | Before | After | Delta |
| :--- | :--- | :--- | :--- |
| **Benchmark (1k lines)** | 10.5s | 2.2s | -80% |
| **Benchmark (5k lines)** | 121s | 8.5s | -93% |
| **Benchmark (50k lines)** | 887s | 56s | -94% |
| **Benchmark (400k lines)** | timeout | 777s | (within time limit) |

**OPW-6045513**

Forward-Port-Of: odoo/odoo#262717
Forward-Port-Of: odoo/odoo#257829

**Steps to reproduce:**
- create a new company A
- in the branch tab, create a new branch A for this company
- create a warehouse for the company A and a warehouse for 
the branch A
- from the company A, in settings for the 'fiscal localization' set 
Package : Generic Chart of account, if not already set
(to have account journals).

From the branch A:
- create a storable product with standard perpetual category
- set a cost of 10
- confirm a PO for 10 and validate delivery
- navigate to 'inventory valuation'

Make sure the branch A is the main company, but 
both branch A and company A are selected: 
- click on generate entry
- click on the 'Other Info' tab

**Current behavior:**
The company of the account move is the parent company
(Company A)

**Expected behavior:**
It should be the branch A. 
(As it is the case if only branch A is selected when clicking 
on "Generate entry")
IAs a consequence, f you click on 'Inventory Valuation' on the 
top left to go back to the view, you will have an access error. 

**Cause of the issue:**
When computing the company_id on the account move, 
move.journal_id.company_id will be the parent company because 
the journal_id of the branch is the one of the parent company 
(by default).
So we will call _accessible_branches() on the parent company.
https://github.com/odoo/odoo/blob/661ddbb7f12e32394a3c11b5a4cd2f38a9e156f5/addons/account/models/account_move.py#L878-L881
Inside __accessible_branches(), 'accessible' will be based on 
self.env.companies 
https://github.com/odoo/odoo/blob/661ddbb7f12e32394a3c11b5a4cd2f38a9e156f5/odoo/addons/base/models/res_company.py#L430-L439
(which is based on 'allowed_company_ids' in the context.
https://github.com/odoo/odoo/blob/661ddbb7f12e32394a3c11b5a4cd2f38a9e156f5/odoo/orm/environments.py#L266)
So the return value of __accessible_branches()
will be a list with 2 ids, the one of the parent 
company and the one of the branch. 
And we will use the first element of this list,
which will be the parent company_id, in _compute_company_id
to set the company of the account move.

**fix:**
When fetching the data for the inventory valuation view, 
only the data from the main company selected matters,
https://github.com/odoo/odoo/blob/dd84309df7fd39e9e97ed02d135d25b211085135/addons/stock_account/report/stock_valuation_report.py#L13

The idea of the fix is to do the same in action_close_stock_valuation
when creating the account move.
We already did something very similar in this PR
https://github.com/odoo/odoo/pull/262776 where we also 
modified the context in action_close_stock_valuation()
before calling _action_close_stock_valuation()
https://github.com/odoo/odoo/blob/43f5ceadbc1f7df9898c327bf65bffdbe9860c1c/addons/stock_account/models/res_company.py#L56

opw-6144294

Forward-Port-Of: odoo/odoo#265369
Forward-Port-Of: odoo/odoo#263828

**Problem:**
Adding a single-value attribute to a product template that has variants with manually-set sales prices wipes those prices, resetting each variant back to the template's base list_price.

**Steps to reproduce:**
1. Create a template "Cable" with attribute Length [1m, 5m, 10m, 15m] (template list_price=1.0).
2. On each variant, manually set a unique Sales Price (10/20/30/40).
3. Add a single-value attribute (e.g. Brand=MELODIKA) to the template.
4. Observe variant Sales Prices.

**Current behavior:**
All four variant prices are reset to 1.0 (the template list_price). Variant ids are unchanged.

**Expected behavior:**
Variant prices remain at the manually-set values, since no variant is created or removed.

**Cause of the issue:**
In 19.x, product.product.lst_price is a stored compute with readonly=False, allowing per-variant overrides. The single-value branch of product.template._create_variant_ids writes
product_template_attribute_value_ids on each existing variant to attach the new attribute. That write invalidates the variant's price_extra (One2many depends), which in turn invalidates the stored lst_price compute. On the next flush, lst_price is recomputed as list_price + price_extra, overwriting the user override.

**Fix:**
Snapshot each variant's lst_price before the single-value-attribute write loop and restore the snapshot afterwards if the recompute changed it. This preserves user-set per-variant prices in the case the loop already exists to handle (single-value attribute that does not require recreating variants). Trade-off: if the single-value attribute itself carries a non-zero price_extra and the user had manual overrides, the extra will not auto-propagate to overridden variants. That is preferable to wiping the override entirely, which is the reported regression.

opw-6229147

**Problem:**
A combo product's parent line appears in the "Invoiced Not Delivered" report (Accounting > Review) and stays there permanently, even after all of its combo items are delivered.

**Steps to reproduce:**
1. Create a combo product bundling two storable items.
2. Sell the combo on a sale order, confirm and invoice it.
3. Deliver every combo item.
4. Open Accounting > Review > Invoiced Not Delivered.

**Current behavior:**
The combo parent line is listed. While items are partially delivered, both the parent and the items are listed, duplicating the same information.

**Expected behavior:**
The combo parent is not listed; only the combo item lines, which carry the real delivery state, appear when they are genuinely not delivered.

**Cause of the issue:**
A combo parent is a virtual sale order line with no stock move of its own, so its delivered quantity is never advanced and always reads 0. The accrual report selects lines where
`qty_invoiced_at_date > qty_delivered_at_date`, so the parent (which does receive an invoiced quantity from the combo logic) matches forever.

**Fix:**
Combo parents carry no delivery information of their own, so excluding them from the accrual search domain is more accurate than inventing a delivered quantity for them. Their combo item lines already represent the real delivery state, so the report stays correct.

opw-6215110

Forward-Port-Of: odoo/enterprise#118942

**Description of the issue this PR addresses:**
----------------------------------------------
Visitors in livechat can trigger partner mention suggestions by typing the @ delimiter in the composer. However, visitors can only mention themselves or odoobot, which does not provide meaningful functionality in the context of a livechat conversation.

**Current behavior before PR:**
----------------------------------------------
- Visitors can type @ in the livechat composer and trigger partner mention suggestions.
- The suggestions only include the visitor themselves or odoobot.

**Desired behavior after PR is merged:**
----------------------------------------------
- The @ delimiter is disabled for visitors in livechat threads.
- Partner mention suggestions are no longer triggered for visitors.
- Internal users (operators) can still use @ mentions normally.

Task-5119068

----------------------------------------------
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Forward-Port-Of: odoo/odoo#267788
Forward-Port-Of: odoo/odoo#253551

When the cogs are computed using the Stock Moves values, we would not differentiate between deliveries and returns, taking both in the cogs value computation. This meant that when doing multiple deliveries with returns before posting the invoice, if the deliveries/returns had different cost, the COGS would be an average of all of them. Example: Delivery $10 -> Return $10 -> Delivery $20  ==>  COGS $13.33

## HOW TO REPRODUCE
- Create Product FIFO Perpetual, cost=10, onHand=1
- Create Sale order for 1 unit
- Deliver and return
- Change cost from 10 to 20:
  - Set on hand to 0
  - Change product cost to 20
  - Set on hand to 1
- Duplicate SO delivery and validate
- Create and Post Invoice => COGS == 13.33


## FIX EXPLANATION

Returns / Refunds are counted negatively.
So when we compute the moves value, instead of doing `(10 + 10 + 20) / (1 + 1 + 1)`, we do `(10 - 10 + 20) / (1 - 1 + 1)`.
We need to propagate this logic to the cogs quantity, so that we don't believe that we invoiced 3 units while only 1 (1-1+1) was delivered.

---

Note:
For the update in test `test_fifo_delivered_invoice_post_delivery_with_return`, I put back the original values modified by 5978bc5dc683d317f4ab87f6c9c9d843568bf4ea

---

<img width="1852" height="363" alt="image" src="https://github.com/user-attachments/assets/ea9f16b2-a818-4c21-b3c3-aa296792f477" />
<img width="1203" height="787" alt="image" src="https://github.com/user-attachments/assets/7348d15a-b840-4ee0-b1da-2b954cdb3d5e" />

---

## Test result without fix:
```
2026-05-28 11:57:45,899 36667 INFO oes_test_19.0 odoo.addons.sale_stock.tests.test_anglo_saxon_valuation: Starting TestAngloSaxonValuation.test_fifo_invoice_with_delivery_with_return ... 
2026-05-28 11:57:47,138 36667 INFO oes_test_19.0 odoo.addons.sale_stock.tests.test_anglo_saxon_valuation: ====================================================================== 
2026-05-28 11:57:47,138 36667 ERROR oes_test_19.0 odoo.addons.sale_stock.tests.test_anglo_saxon_valuation: FAIL: TestAngloSaxonValuation.test_fifo_invoice_with_delivery_with_return
Traceback (most recent call last):
  File "/home/odoo/Odoo/src/19.0/odoo/addons/sale_stock/tests/test_anglo_saxon_valuation.py", line 1099, in test_fifo_invoice_with_delivery_with_return
    self.assertRecordValues(invoice.line_ids, [
  File "/home/odoo/Odoo/src/19.0/odoo/odoo/tests/common.py", line 727, in assertRecordValues
    self.assertSequenceEqual(expected_reformatted, record_reformatted, seq_type=list)
AssertionError: Lists differ: [{'ac[22 chars]t': 0, 'credit': 50}, {'account_id': 9141, 'de[114 chars]: 0}] != [{'ac[22 chars]t': 0.0, 'credit': 50.0}, {'account_id': 9141,[132 chars]0.0}]

First differing element 2:
{'account_id': 9138, 'debit': 0, 'credit': 20}
{'account_id': 9138, 'debit': 0.0, 'credit': 13.33}

- [{'account_id': 9162, 'credit': 50, 'debit': 0},
+ [{'account_id': 9162, 'credit': 50.0, 'debit': 0.0},
?                                   ++           ++
-  {'account_id': 9141, 'credit': 0, 'debit': 50},
+  {'account_id': 9141, 'credit': 0.0, 'debit': 50.0},
?                                 ++             ++
-  {'account_id': 9138, 'credit': 20, 'debit': 0},
?                                 ^^
+  {'account_id': 9138, 'credit': 13.33, 'debit': 0.0},
?                                 ^^^^^           ++
-  {'account_id': 9168, 'credit': 0, 'debit': 20}]
?                                             ^^
+  {'account_id': 9168, 'credit': 0.0, 'debit': 13.33}]
?                                 ++            ^^^^^

```

---

OPW-6213321

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Forward-Port-Of: odoo/odoo#266917

Scenario:

- paste "język việt" (polish + vietnamese) in a page
- change website font to not be "Noto Sans", for example: Raleway
- open the page on Edge Browser on Android

Result: polish and vietnamese characters are using different font and
are visually different than latin character.

Cause: google fonts is serving for nearly all browsers font
configuration with woff2 files and unicode-range so the user only loads
the part of the font that will be used on the website. For Edge browser
on android, based on the user-agent chrome is serving only a TTF file
without unicode-range because it is thinking that unicode-range is not
supported. These files only contain basic latin characters, so extended
latin and vietnamese characters are being rendered with fallback "Odoo
Unicode Support Noto" that has a different weight and style for the same
weight.

Fix:

For the browser not supporting unicode-range (desktop edge before 2020,
Edge on android, …), in addition to latin we ask google fonts to
provide([1]) latin-extended and vietnamese subsets in TTF/WOFF files if
available. For other subset (hebrew, arabic, cyrillic, …) the intent is
to fallback on "Odoo Unicode Support Noto" since they should usually not
be mixed with latin characters.

Note: Edge on android in reality support unicode range, so this would be
solved if google fonts just served the unicode range font configuration
for that user-agent.

[1]: https://developers.google.com/fonts/docs/getting_started#specifying_script_subsets

opw-4642242

Forward-Port-Of: odoo/odoo#267798

Issue:
Sending payments to SAT before its full amount is reconciled allow sending the same invoice payment several times to CFDI.

Steps to reproduce:
- In a Mexican company
- Create an invoice A of $40 to Inmobiliaria CVA
- Confirm and send to CFDI
- Go to bank, create a new Bank transaction of $80
- reconcile with Invoice A
- Go to invoice A => click on button "Update payments" (it doesn't appear in previous versions)
- Then sheet CFDI and Download There is the first XML sent to CFDI with payment for invoice A
- Create an invoice B of $40 to Inmobilira CVA
- Confirm and send to CFDI
- reconcile the transaction with Invoice B
- Go to invoice B
- Click on button "Update payments"
- Then sheet CFDI and Download There is the second XML sent to CFDI with payment for invoices A and B

Invoice A payment was sent twice to CFDI

Expected behavior:
- The "Update payment" button should appear only once the invoice payment is fully reconciled.

Current behavior:
- The update payment button appear once the invoice is reconciled with a payment.

The method `_l10n_mx_edi_cfdi_invoice_get_payments_diff` is called twice, once to check whether it's needed to display the "Update button" and once when you try to update the payment (called only after clicking on said button).

opw-5432421

Forward-Port-Of: odoo/enterprise#118850
Forward-Port-Of: odoo/enterprise#108355

**Problem:**
If a vendor bill associated with a project through its analytic distribution has lines with negative subtotals, those lines are not considered in the project profitability report. An example use case is a downpayment invoice, followed by a final invoice with the downpayment amount deducted.

**Steps to Reproduce:**
- Ensure project_purchase is not installed
- Create a new project with "Billable" enabled
- Go to the project settings and create an analytic account
- Create and post a vendor bill with a line labeled "downpayment", the analytic account set, and a unit price of 5
- Duplicate the vendor bill, set the "downpayment" line unit price to -5, add a line labeled "product" with the analytic account set and a unit price of 10, and post the bill

-> Go to the project updates and see that the vendor bill costs is wrong (15)

**Solution:**
A similar bug affecting customer invoices was resolved in PR #130992. AMLs with non-zero subtotals should be considered, so the domain is adjusted accordingly.

opw-6172523

Forward-Port-Of: odoo/odoo#265378

<h2>Context</h2>

Clients can have some existing accounts with `reconcilable` flag set as True. Some of these accounts also have partially reconcilated transactions. In Odoo 19.0, it is not authorized to toggle the `reconcilable` flag from True to False on accounts that contain partially reconcilated transactions.

When the migration script `l10n_pl/migrations/2.1/end-migrate.py` is executed, it tries to update the CoA by adding/updating accounts, using the accounts in the file `l10n_pl/data/template/account.account-pl.csv`. This CSV file contains a reconcilable flag per account.

<h2>Problem</h2>

Before this modification, the upgrade script was trying to update the CoA using `_load_data`, which tries to overwrite the reconcilation flag of accounts in the client DB. A traceback occurs during the upgrade if an account's `reconcilable` flag is toggled from True to False during the update of the CoA, while it still contains partially reconciled transactions.
<details>

<summary>Traceback</summary>

```
File "/home/odoo/src/odoo/19.0/addons/l10n_pl/migrations/2.1/end-migrate.py", line 8, in migrate
    Template._load_data({'account.account': Template._get_account_account('pl')})
  File "/tmp/tmpm8z3nlb0/migrations/account/0.0.0/pre-ensure-deferred-accounts.py", line 36, in _load_data
    return super()._load_data(data, *args, **kwargs)
  File "/home/odoo/src/odoo/19.0/addons/account/models/chart_template.py", line 697, in _load_data
    created_records[model] = self.with_context(lang='en_US').env[model]._load_records(all_records_vals)
  File "/home/odoo/src/odoo/19.0/odoo/orm/models.py", line 5171, in _load_records
    data['record']._load_records_write(data['values'])
  File "/home/odoo/src/odoo/19.0/addons/account/models/account_account.py", line 1122, in _load_records_write
    super()._load_records_write(values)
  File "/home/odoo/src/odoo/19.0/odoo/orm/models.py", line 5092, in _load_records_write
    self.write(values)
  File "/home/odoo/src/odoo/19.0/addons/account/models/account_account.py", line 1045, in write
    self.filtered(lambda r: r.reconcile)._toggle_reconcile_to_false()
  File "/home/odoo/src/odoo/19.0/addons/account/models/account_account.py", line 975, in _toggle_reconcile_to_false
    raise UserError(_('You cannot switch an account to prevent the reconciliation '
odoo.exceptions.UserError: You cannot switch an account to prevent the reconciliation if some partial reconciliations are still pending.
```

</details>

<h2>Solution</h2>

I have sanitized the dict `data` using the `_pre_reload_data` method, so that the traceback does not appear anymore when upgrading. 

<h3>Notes</h3>

`_pre_reload_data` method sanitizes the dict `data` by avoiding the creation of duplicated accounts, the creation of duplicated fields for a given record, the toggling of the `reconcilable` flag, etcs.


---
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Forward-Port-Of: odoo/odoo#257006