Disable “Apply suggestion” button if MR suggestion is not applicable

Problem to solve

If a suggestion become out of date and cannot be applied, the apply button is simply not shown. This is very confusing.

Proposal

Today we can only say to the user that the suggestion is not appliable, not the why. There can be various reasons (see thread). So, for now, we can only show the disabled Apply suggestion button with a tooltip saying Can't apply suggestion.

Next iteration

Once we're able to pass the specific reasons, we can draft some good tooltip messages to precisely explain the why: #219455 (closed)

Links / references