[Bug][Android] Deleting the auto-inserted trailing space after a mention strips the mention to plain text

[lukasz-patalan]

Describe the bug

On Android, deleting the trailing whitespace that is automatically inserted after a completed mention removes the mention (its span is stripped and it becomes plain text). Once stripped, the span is never restored, so the text stays as a regular @uniqueTag string with no mention styling and no tag in the emitted HTML.

To Reproduce

• The mention is inserted as @XYZ followed by an auto-inserted trailing space @XYZ
• Press backspace once to delete that trailing space.
• The mention loses its styling and turns into plain text; the emitted HTML no longer contains a tag.

onChangeHtml output across the steps:

after selecting the user (note trailing space)

<p><mention text="@pelargonia0001-test1" indicator="@" userId="user_3DIRyZz9CM7JO7VMsti66T83vKD" uniqueTag="pelargonia0001-test1">@pelargonia0001-test1</mention> </p>                                                                                                                                        

after deleting the trailing space (mention gone)

<p>@pelargonia0001-test1</p>     

Expected behavior

Deleting whitespace adjacent to a completed mention should not silently strip the mention. The mention should either stay intact or be deleted as a whole atomically (as it behaves on iOS).

Video:

Screen_Recording_20260710-162052_HOBB.Dev.mp4

Device:

Device: Android (reproducible on both physical device and emulator)
OS: Android

Additional context

Reproducible 100% on Android; not reproducible on iOS, where editing a mention removes the whole mention range instead of leaving orphaned plain text.
Pressing Enter right after the mention does not trigger it; only editing that reaches into the mention's word range does (e.g. deleting the trailing space).