Affected versions

• 88.0a1(2021-03-03), 87.0b5

Affected platforms

• Windows 10

Steps to reproduce

1. Launch Firefox, access the Customize page and add the Profiler tool to the overflow;
2. Click on the overflow button;
3. Click on the Profiler > to expand the settings section;
4. Observe then click the Settings picker dropdown button;

Expected result

• button is centered;

Actual result

• button is centered only after the click;
• max-length values might need revision as well to best fit in the section;

Regression range

• not a regression, issue was visible with initial implementation;
• First bad: 2020-03-25;
• Last good: 2020-03-24;
• Pushlog: URL
• Potential regressor: bug 1572786;

Additional notes

• macOS 10.15 appears to not be affected;
• issue reproducible with OS recommended and 800x600 resolution;
• attached recording with the issue.

Moving component given bug 1572786 implemented this.

The problem might be around this code: https://searchfox.org/mozilla-central/rev/9043e515e9608cc55b252a40cb2dfb6f767bcffd/devtools/client/performance-new/popup/panel.jsm.js#248-267

It's not 100% clear to me if we still need this. I think this is because of the collapsible information at the top of the panel, but I'm not sure.