Refactor merge diffs comment button to be more accessible
Related to !58692 (merged)
Background
During the bug fix to make the comments bubble draggable in Firefox we had to stop using an actual "button" and started using a div with "button-like" properties.
This exposed issues with accessibility, testing, and basic code maintainability.
We need to refactor the current implementation into something more accessible that does not have the dragging problems associated with empty buttons in Firefox.
Possible solutions
The main issue is that without any "visible" content inside a button Firefox cannot make it that button draggable. This regression started when we removed the gl-icon
component for performance reasons.
We could get back to our previous accessible state by using a button again, an image inside the button without using a child component. This would fix Firefox, but the performance aspect needs to be investigated.
Alternatively, we could spend some time researching alternatives like links that can accomplish the same thing visually, but come with more baked in accessibility. Of course links would not be semantically accurate as they do not actually navigate anywhere.