I’m a big fan of Firefox’s mini grid view in the web inspector, which provides
a small version of the currently overlaid grid, which is in proportion to the real thing.
Hovering over the different areas of the mini grid causes the equivalent area on the grid overlay to also highlight, along with a tooltip containing useful information such as the dimensions of that area, its row and column numbers, etc. [my emphasis]
It bugs me to no end, though, that the tooltip emphasised in the quote does not appear if the highlighted grid row/column is too close to the viewport’s edge. Instead of adjusting for this by moving the tooltip into view, the behaviour seems to be just to not show it at all, which rather defeats the purpose – especially when, as far as I know, this tooltip is the only way to see the calculated size of empty grid tracks.
I can’t find any bugs regarding this on Bugzilla, but then I can virtually never find anything on there, so there’s a decent chance I’m just bad at searching.
Is there some setting I can’t find that will allow me to see the tooltips even for edge rows/columns? Or if this is just a bug, has it been addressed?
I've tested this in Firefox 98.0 and could reproduce it. As this is definitely a bug in the Firefox DevTools and I couldn't find one either in Bugzilla, I now created a bug report for it.