vertical-align:middle is different from centered alignment in XUL, as the former depends on the font metrics which can have unequal padding at the top and the bottom. Enabling DirectWrite shows this problem or even just increasing the font size regardless of DirectWrite. vertical-align:middle on the tab stack is also wrong for the progress line which isn't supposed to be centered. So instead we need to make sure that the tab-content container has the same height for app tabs and normal tabs. Squeezing the label instead of completely removing it achieves this.

Comment on attachment 476204 [details] [diff] [review] patch Changing the vertical align seems to actually make the favicon alignment worse... http://grab.by/6r3i http://grab.by/6r3x

(In reply to comment #2) > Comment on attachment 476204 [details] [diff] [review] > patch > > Changing the vertical align seems to actually make the favicon alignment > worse... > http://grab.by/6r3i > http://grab.by/6r3x 6r3i is with the patch and 6r3x without it? tab-content has align="center", so this should take care of the alignment as long as the box height for app tabs is the same as for normal tabs. This worked for me on Windows and Linux, but maybe there's something Mac-specific that I'm missing.

Both screenshots have the .tab-label[pinned] hunk applied. 6r3i includes the change to "vertical-align: top" for .tab-stack, 6r3x does not.

this should fix pinstripe

This needs to be fixed sooner than right before RC, ideally for beta 8. This is a central piece of CSS, I don't want to see more theme changes building on the misalignment. Also, this will affect third-party themes. Also, if for some reason this doesn't always work as expected, we'd want to find out about it as soon as possible.

Good points. I final+'d it as polish, but you're right that themers could compound the problem here if they treat it as given. I agree that beta8 would be ideal, but I wouldn't hold a specific beta for it, so bumping to betaN

(In reply to comment #6) > This is a central piece of CSS, I don't want to see more theme changes building > on the misalignment. Happening in bug 597592 right now :/

Comment on attachment 476496 [details] [diff] [review] patch v2 Can you add a comment explaining where the 19px comes from?

I'd like to land this for beta7 in preparation for bug 597592, which is wanted for that beta.

Comment on attachment 479366 [details] [diff] [review] patch v2 (comment added) bug 597592 now blocks beta 7.