I see this with "2712:5: Using the result of an assignment as a condition without parentheses (fixes available)" but the behavior I'm reporting probably happens with other warnings.
This warning is triggered by code like this:
The warning puts a little yellow triangle in the left margin, and a light bulb at the end of the line that invokes fixits:
Prior to 7.01 clicking on the lightbulb presented a popup with two fixit choices: either replace "=" with "==" or to enclose the assignment in parens to show that the assignment is intentional. In 7.01 if I click the lightbulb, it simply applies the conversion to "==". I did this recently and didn't notice the problem, creating a bug that was very hard to see!
Further, hoviering over the yellow triangle puts up a tooltip-like window with info about the warning:
The blue text is a link, clicking the link applies BOTH fixits:
Now I have two clangd warnings!
Our application is very old and has a ton of these. I use the fixit to enclose in parens every day!