Affected versions

• 71.0a1 (2019-09-29)

Affected platforms

• All available

Steps to reproduce

1. Launch Firefox;
2. Set devtools.netmonitor.features.requestBlocking to true in about:config;
3. Access any webpage, press F12 to open the DevTools inspector and select Network tab;
4. Block any request so that the Blocking UI is enabled;
5. Click and drag over "Search" or "Request Blocking";

Expected result

• "Search" and "request Blocking" are not draggable.

Actual result

• "Search" and "Request Blocking" are draggable.

Regression Range

• Not a regression, only visible after implementation of bug 1580728;

Additional notes

• Attached a recording with the issue;
• It seems that devtools expects the user to drag a .har file. If dragged to the tab bars, the drag is seen as a tab drag.

Thanks for the report!

I can't reproduce on Win10, is this MacOS only?

Honza

Hi Jan, the screencast is from a Windows 10 system. Another thing that I saw is that they are draggable from the edges and not from the middle.

OK, I can reproduce it now.

Honza

Honza; Do you know why this is happening? Any background information here?

Bugbug thinks this bug is a regression, but please revert this change in case of error.

I think that it's because the tab is rendered using <a>
https://searchfox.org/mozilla-central/rev/5e830ac8f56fe191cb58a264e01cdbf6b6e847bd/devtools/client/shared/components/tabs/Tabs.js#316

Note that the Toolbox panel is using <button>
https://searchfox.org/mozilla-central/rev/5e830ac8f56fe191cb58a264e01cdbf6b6e847bd/devtools/client/framework/components/ToolboxTab.js#68
So, perhaps an option?

Honza

https://hg.mozilla.org/mozilla-central/rev/b059658718c9

Verified with 71.0b4 on the mentioned platforms.