Bug 217611

Summary: Javascript regex(?) locks up tab for 30ish seconds
Product: WebKit Reporter: Tim Lange <mail>
Component: WebKitGTKAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: aperez, bugs-noreply, webkit-bug-importer
Priority: P2    
Version: Other   
Hardware: PC   
OS: Linux   
Attachments:
Description Flags
Timeline Screenshot none

Description Tim Lange 2020-10-12 08:44:24 PDT
Created attachment 411120 [details]
Timeline Screenshot

Hi,

on both moodle instances of my university WebKitGTK the tab gets unresponsive for like 30 seconds. This does not happen in Safari, Chrome or Firefox.

This issue is also reproducible for me on the moodle demo instance:
1. https://sandbox.moodledemo.net
2. Login as student
3. Load the dashboard (https://sandbox.moodledemo.net/my/)

I already tried running Epiphany with WEBKIT_DISABLE_COMPOSITING_MODE=1, but the problem persists.

OS: Fedora 32, Epiphany 3.36.4
HW: PC with i5-3570k/T470 with i5-7200u

I attached a timeline showing the function that takes unusually long.

Kind Regards
Tim
Comment 1 Adrian Perez 2020-10-28 15:51:29 PDT
Hi Tim,

(In reply to Tim Lange from comment #0)
> Created attachment 411120 [details]
> Timeline Screenshot
> 
> Hi,
> 
> on both moodle instances of my university WebKitGTK the tab gets
> unresponsive for like 30 seconds. This does not happen in Safari, Chrome or
> Firefox.
> 
> This issue is also reproducible for me on the moodle demo instance:
> 1. https://sandbox.moodledemo.net
> 2. Login as student
> 3. Load the dashboard (https://sandbox.moodledemo.net/my/)
> 
> I already tried running Epiphany with WEBKIT_DISABLE_COMPOSITING_MODE=1, but
> the problem persists.

The issue does not seem reproducible with WebKitGTK 2.30.2, nor with a
recent “trunk” build.

> OS: Fedora 32, Epiphany 3.36.4
> HW: PC with i5-3570k/T470 with i5-7200u

Could you indicate which version of WebKitGTK is Epiphany using? You
can find it in the “About” dialog. I suspect it will be 2.28.x; in that
case, does the issue disappear when you use a newer version of WebKitGTK?
Comment 2 Tim Lange 2020-11-01 11:41:21 PST
(In reply to Adrian Perez from comment #1)
> Hi Tim,
> 
> (In reply to Tim Lange from comment #0)
> > Created attachment 411120 [details]
> > Timeline Screenshot
> > 
> > Hi,
> > 
> > on both moodle instances of my university WebKitGTK the tab gets
> > unresponsive for like 30 seconds. This does not happen in Safari, Chrome or
> > Firefox.
> > 
> > This issue is also reproducible for me on the moodle demo instance:
> > 1. https://sandbox.moodledemo.net
> > 2. Login as student
> > 3. Load the dashboard (https://sandbox.moodledemo.net/my/)
> > 
> > I already tried running Epiphany with WEBKIT_DISABLE_COMPOSITING_MODE=1, but
> > the problem persists.
> 
> The issue does not seem reproducible with WebKitGTK 2.30.2, nor with a
> recent “trunk” build.
> 
> > OS: Fedora 32, Epiphany 3.36.4
> > HW: PC with i5-3570k/T470 with i5-7200u
> 
> Could you indicate which version of WebKitGTK is Epiphany using? You
> can find it in the “About” dialog. I suspect it will be 2.28.x; in that
> case, does the issue disappear when you use a newer version of WebKitGTK?

It's using WebKitGTK 2.30.1. The issue disappeared when using Epiphany 3.38.1. I don't really understand why because the About dialogs say it is using the same WebKitGTK version. Anyways it works now as expected :)