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Xperf shows shows xul.dll as a culprit for slow Thunderbird

Wayne Mery replied
Orlinbo

Hello, On Windows 10 and 11 - and on Linux, Thunderbird is slow with my gmail account. I proceed to see what is the issue and used Xperf (Microsoft's Windows Performance Analyzer). Please see attached image. Hope this helps!

Hello, On Windows 10 and 11 - and on Linux, Thunderbird is slow with my gmail account. I proceed to see what is the issue and used Xperf (Microsoft's Windows Performance Analyzer). Please see attached image. Hope this helps!
Attached screenshots

All Replies (1)

1. Slow at doing what? 2. What's happening in Tools > Activity Manager?