Scrolling is not smooth but lags

[gurpreetshanky]

• VSCode Version: Vscode Insiders ,Vscode Stable
• OS Version: Windows 10 (Fast Ring)

Steps to Reproduce:

1. Launch vscode
2. If minimize, scrolling shutters after maximize

Does this issue occur when all extensions are disabled?: Yes

This is a duplicate of #13612 but I couldn't post it there as it was closed.

Comment from @bpasero:
Depends on electron/electron#8960 (comment)

[bpasero]

@gurpreetshanky What is your windows version? Copy it from running winver.exe

[gurpreetshanky]

Version 1809 ( OS Build 18267.1001)

[bpasero]

@gurpreetshanky interesting, that should be Windows 10 RS5. Can you give more details about:

• what device are you using
• how do you scroll (external mouse or touchpad)
• does it reproduce if you use Code (stable) and configure the smoothScrollingWorkaround to true

[gurpreetshanky]

This is the Dell XPS 15 with Microsoft Precision touchpad.
No it doesn't works with smoothscrollingworkaround.

This is the same bug which I have linked #13612. Most probably, it has returned in insider version of Windows.

[bpasero]

@gurpreetshanky that would be bad, any chance you could test the non-insiders version?

[gurpreetshanky]

Yes this problem is not present in stable version on turning smoothScrollingWorkaround true. Has smoothScrollingWorkaround setting is removed in insiders version? I cannot find it.

[bpasero]

@gurpreetshanky yes I removed it assuming that this issue was fixed in Windows 10 RS5. It is unlikely I would bring it back, we should rather find out why this is broken again in Windows insiders. I wonder if your insiders version is somehow behind the RS5 update.

I actually meant to ask if you could try a Windows Stable version.

[gurpreetshanky]

@bpasero No mine is fast ring(18267), so its after the RS5 update. This bug definitely came back in new Windows Insiders version.

[bpasero]

I will follow up with the developer that pushed the fix to ask if this possibly had to be reverted for some reason

[rossnichols]

@gurpreetshanky, can you please collect a trace of the issue?

1. Download inputcore.wprp from https://1drv.ms/u/s!At5lGHRE4ciEmP5qkuoKdpJ8w0-eZA
2. Open administrator command prompt in directory containing that file
3. Run: wpr -start inputcore.wprp
4. Reproduce the scrolling issue
5. Run: wpr -stop repro.etl
6. Share the repro.etl file here

[gurpreetshanky]

@rossnichols here is the file https://1drv.ms/u/s!AgmFl0OpBO1agYtxQUmHZHEtPL8dlg

[rossnichols]

@gurpreetshanky thanks! Root cause is known, I'll work with Ben on getting VSCode fixed.

[Lottae-Siri]

So, What is the conclusion after you have know root cause. Do I need also to follow your step below to solving problem or I have to wait for your fixed VSCode untill release its in next patch.

[rossnichols]

@korpong753, you don't need to follow the instructions, I have all the information I needed. You'll just have to wait until VSCode has an update that fixes it.

[Lottae-Siri]

@rossnichols, I'm not sure, Is it bug of VSCode or not, Once we have checked and updated window 10 pro, now we can use touchpad with smoothly without lag problem anymore.

This is window version that we updated. (https://support.microsoft.com/th-th/help/4462933/windows-10-update-kb4462933)

[rossnichols]

@korpong753, can you collect a trace using the instructions above?

[HazemAM]

@rossnichols I can confirm scrolling is much better with a precision touchpad after the KB4462933 update with minimal lagging (still lags a little bit, but it's not affected by VSCode's focus change, AFAICT).

Windows & VSCode both on stable.

Edit: This is the related change in the update:

Addresses an issue that may cause an application that has a child window to stop processing mouse inputs. This issue occurs when a precision touchpad triggers a WM_MOUSEWHEEL event.

[bpasero]

@gurpreetshanky can I ask you if the scroll-lag workaround setting in VSCode fixes the issue for your? Just configure:

• window.smoothScrollingWorkaround: true
• window.titleBarStyle: native

[gurpreetshanky]

@bpasero Yes it has fixed the issue for me by these workarounds.

[bpasero]

@gurpreetshanky @korpong753 @HazemAM can you help me to test a new build with the fix from https://chromium-review.googlesource.com/c/chromium/src/+/1299342 to see if it works now without having window.smoothScrollingWorkaround: true configured?

Steps:

• close any Code instances
• download
• open settings and configure window.smoothScrollingWorkaround: false
• restart Code
• see if scrolling is smooth

[gurpreetshanky]

@bpasero Honestly I tried both the Insiders versions (normal and above provided one) and checked multiple times. The workaround was not required in both situations.

[bpasero]

@gurpreetshanky great, thanks for confirming. By now the current insiders version and the one I linked will both have the fix included 👍

[bpasero]

Closing this issue given that we plan to release VSCode stable early February with Electron 3.x. If you want to benefit from the fix already, consider to use our insiders version that already contains the fix: https://code.visualstudio.com/insiders/