**Issue 1:**

Steps to reproduce:
- Insert a icon in an empty paragraph.
- Remove the inserted icon.
- The paragraph becomes unreachable.

Cause:
- When a paragraph contains only an icon, removing that icon during the delete process does not trigger `fillEmpty`. As a result, the paragraph ends up with no content, leaving it empty and unreachable.

Solution:
- During the delete process, after the icon is removed, call the `fillEmpty` method. This ensures that if the block becomes empty, a `<br>` is inserted inside the paragraph, keeping it accessible.


**Issue 2:**

Steps to reproduce

- Insert an icon in an empty paragraph.
- Place the cursor before the icon.
- Press Enter.
- Nothing happens.

Cause
- When the cursor is placed before a `contenteditable=false` element, `getDeepRange` sets the selection deep inside the non-editable element as a result, when Enter is pressed, the action is ignored because the selection is not in an editable context.

Solution

- Instead of setting the selection inside `getDeepRange`, set the selection after calling `getDeepRange` only if the returned range is not within a `contenteditable=false` element.

task-3540454

Forward-Port-Of: odoo/odoo#241052
Forward-Port-Of: odoo/odoo#237891