Using the current modern theme, I'm getting a "halo"/extended border around any button - see attached image for before & after. Started sometime after 2008020101, but probably more than a few days ago. Its very annoying and looks rubbish. I couldn't see anything obvious in DOMI to be able to track down the problem.

I know why this is. -moz-border-XXX-colors: transparent used to be really transparent. Now it shows the element's background colour instead (by comparison border-color: transparent already shows the background colour). What we have to do now is to turn the transparent border into extra margin and use an outline instead. Fortunately this will actually end up simplifying some of the rules a bit.

OK, so this turned out to be slightly more complicated. The original border was six pixels wide. For the top and left borders: The inner pixel is #B1BBC9 for normal buttons and #899AAC for active buttons. The second pixel is #BBC6D1 for normal buttons and #8290A5 for active buttons. The third pixel is black. For default buttons, the fourth pixel is black too. The next two pixels are transparent, or #98A5B2 if the button is focused. Except for default buttons, the last pixel is transparent. The focus is easily translated into an outline, however dealing with default buttons is trickier. There appear to be two alternatives: 1. Replace transparent with #C7D0D9 (default window background). 2. Add an extra pixel of padding to all non-default buttons.

Oh, and the problem with varying the margin is the min-width.

This makes non-default buttons slightly bigger, so that there's no size change when you add or remove the default attribute (<dialog>s do this). (Very narrow buttons will still be a few pixels wider still because the margin is larger.)

This version changes the min-width to 60px so that I can keep the behaviour of default buttons being slightly larger than non-default buttons.

Comment on attachment 328660 [details] [diff] [review] Change minimum width unit to pixels I prefer the look of this option

Fix checked in.

I'm repoening this since attachment #331071 [details] [diff] [review] hasn't landed on comm-central.

Pushed changeset 970adc6fbada to comm-central.

Another disabled button with a custom margin...

Pushed changeset ac884f31493e to comm-central.

Found some more buttons with width/margin overrides...

Comment on attachment 363087 [details] [diff] [review] Fix search/filter dialogs Pushed changeset 2bf5d08d96b4 to comm-central.