Insert suggestion doesn't work outside the "Changes" tab in merge requests in rich text editor
Context
Reported by @justin_ho in #379045 (comment 1472672908)
Description
I was replying to this comment and tried the "Insert suggestion" button and the text box only flashed without actually adding the code for the suggestion. After switching to plain text to include the suggestion and switching back to rich text, copy-pasting inside the code suggestion block caused it to break into 2 lines: both when copying other code and with plain text (I don't have this part of the bug in the video but can provide one if needed).