>>> My Info: Win7_64, Nightly 48, 32bit, ID 20160330030326 STR: 0. Open devtools, dock it to the right side of window, dock it to the bottom side of window, close devtools. 1. Open Devtools -> Performance 2. Press button "Start Recording Performance". Press it again to end recording. 3. Click "JS Flame Chart" tab to switch to it. 4. Press Ctrl+Shift+D 5. Click "Waterfall" tab to switch to it. 6. Press Ctrl+Shift+D 7. Click "JS Flame Chart" tab to switch to it. Result: After Step 7 selected area in timeline quickly collapses at the end of timeline Expectations: Selected area in timeline should stay still

This is regression from bug 1120623. Regression range: > https://hg.mozilla.org/integration/fx-team/pushloghtml?fromchange=e417e32d9cb698fe0b2e376d9cdeac0c2cffb43f&tochange=7a0ebe3fccacc655c38e7f32948626af4d3d3269

Woo! That one is fun.

Platform triage decision: This is not something that we will block Fx47 release on.

[Triage] Patrick: can you comment on severity here? Thx.

I'll let Greg comment on this one as he knows more about the performance tool (or who to talk to about it), than me.

This only happens when you hit the cmd+d shortcut on that specific view, so the severity seems medium to me. Although I believe it could be a quick fix since you just need to account for the modifiers being used on the shortcuts. It might be worth tackling.

I made the Flame Graph ignore keys with any modifiers and it cleared up the issue.

Comment on attachment 8771980 [details] [diff] [review] Fix shortcut modifier bug with Flame Graph. Review of attachment 8771980 [details] [diff] [review]: ----------------------------------------------------------------- LGTM!

Pushed by cbook@mozilla.com: https://hg.mozilla.org/integration/fx-team/rev/46d964768cf6 Fix shortcut modifier bug with Flame Graph. r=jsantell

Looks like a simple enough change that could be uplifted to aurora and beta in time for the 48 release. Once this lands on m-c, could you please request uplift approvals?

Comment on attachment 8771980 [details] [diff] [review] Fix shortcut modifier bug with Flame Graph. Approval Request Comment [Feature/regressing bug #]: 1261048 [User impact if declined]: The performance tool can break and the graph will begin to act erratic on hitting certain shortcut combinations. [Describe test coverage new/current, TreeHerder]: The flame graph has mochitest coverage for the individual features of the graph here: https://dxr.mozilla.org/mozilla-central/search?q=path%3Adevtools%2Fclient%2Fshared%2Ftest+path%3Aflame&redirect=false and overall integration coverage here: https://dxr.mozilla.org/mozilla-central/search?q=path%3Adevtools%2Fclient%2Fperformance+path%3Aflame&redirect=false [Risks and why]: This is low risk as it adds a small modifier button check to a handler. [String/UUID change made/needed]: None.

Comment on attachment 8771980 [details] [diff] [review] Fix shortcut modifier bug with Flame Graph. Review of attachment 8771980 [details] [diff] [review]: ----------------------------------------------------------------- We'll have 48 beta 10 to mitigate the potential regression. This patch fixes a shortcut regression with Flame Graph. Let's take it in 48 beta 10 and aurora. This also needs to be verified.

I managed to reproduce this issue on Firefox 48.0a1 (2016-03-30) and on Windows 10 x64, using STR from Comment 0. The issue is no longer reproducible on Firefox 48.0b10, Firefox 49.0a2 (2016-07-22), Firefox 50.0a1 (2016-07-21). The tests were performed on Windows 10 x64, Ubuntu 16.04 x64 and on Mac OS X 10.11.1