Lexical version: Assumed 0.24.0 from package here

The common theme appears to be the LexicalTypeaheadMenuPlugin component

Steps To Reproduce

Emoji example:

1. Open Lexical Playground example at https://playground.lexical.dev/
2. Ensure there's a colon with a space before it
3. Set playground to read-only mode
4. Focus cursor after colon
5. Choose an emoji from the list

Same for @-mentions.

Link to code example:

https://playground.lexical.dev/

The current behavior

Emoji/mentions picker opens and allows insertion/modification of nodes

The expected behavior

No picker should be present, or at least no emoji/mention should be insertable

Impact of fix

Ensure true compliance of "read only" mode