User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b5) Gecko/2008032620 Firefox/3.0b5 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b5) Gecko/2008032620 Firefox/3.0b5 <button>FOO</button> and <input type=button value=FOO/> are both 2px smaller width and height than in Firefox 2. Also, probably related, they have a 3px border instead of a 2px border. Reproducible: Always Steps to Reproduce: 1. 2. 3.

Odd. On Linux and Mac this would have been due to native theming, but we had that on with Windows Firefox 2. Martijn, can you reproduce this? If so, can you locate the regression range?

Results on branch, trunk and IE with classic and windowsXP theme: Firefox branch Classic: offsetHeight: 22 -- offsetWidtht: 50 WindowsXP: offsetHeight: 22 -- offsetWidtht: 50 Firefox trunk Classic: offsetHeight: 22 -- offsetWidtht: 50 WindowsXP: offsetHeight: 24 -- offsetWidtht: 52 IE Classic: offsetHeight: 24 -- offsetWidtht: 42 WindowsXP: offsetHeight: 24 -- offsetWidtht: 42

I think this is basically the same as bug 388379. Bug 382147, comment 8 might also contain some useful info on this.

Reporter, any idea why you see different results from Martijn? What do you see on his testcase? If you see the same as him, can you post a testcase that shows your problem?

I'm uploading a testcase and a screenshot of the output on FF3b5 vs. FF2 (Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.14) Gecko/20080404 Firefox/2.0.0.14). I'm on an XP machine with the default theme.

That's consistent with Martijn's results: the trunk rendering is larger (not smaller as described in comment 0). And I agree with Martijn that this is a duplicate of bug 388379.