Help with debugging a bug in Konqueror

[Stefano Crocco]

On lunedì 13 luglio 2026 23:46:33 Ora legale dell’Europa centrale Juraj Oravec 
wrote:
> A small update,
> 
> I can get both Falkon and Konqueror stuck when opening the combobox on
> this page:
> https://google.github.io/liquidfun/
> 
> Best regards,
> Juraj
> 
> On pondelok 13. júla 2026 23:22:46 stredoeurópsky letný čas Juraj Oravec
> 
> wrote:
> > Hello,
> > 
> > > Hello to everyone,
> > > for the last few weeks, I've randomly encountered what I assume is a
> > > bug in Konqueror: I'd like to fix it, because it's rather annoying,
> > > but I don't know how to debug it to find its cause.
> > > 
> > > The issue is that sometimes Konqueror completely freezes: none of
> > > its
> > > windows respond to mouse or keyboard. The only way to go on is to
> > > kill it. It's not a frequent issue: it usually happens once a day or
> > > so. Once it has happened, however, it's likely to happen again in a
> > > short time.
> > 
> > I run experiencing similar issue with Falkon, where Falkon freezes the
> > whole desktop when I try to open a combobox (<select>) on a website.
> > It also happens randomly and everything is fine after I ssh into the
> > machine and kill Falkon. I did not look into debugging this issue yet
> > as I attributed it to "has to be external thing".
> > 
> > I am running i3 + picom on top of XOrg. If you are running something
> > else, it could explain the difference on what freezes. After Falkon
> > dies system is fully responsive again.
> > 
> > I attributed it to Qt or Intel drivers (I have Intel B580 gpu), as
> > they are not perfect yet (the HW video acceleration likes to crash
> > once in a while).

Thanks for this information. I tried the link you provided and indeed, I got a 
freeze. However, as you said, this freezes the whole desktop, while in the 
other cases (luckily) I always experienced a freeze of Konqueror only. The two 
backtraces look very similar, however, except for the beginning. I attach the 
relative backtrace.

Do you get the freeze every time on the page you mentioned? I only got it on 
my desktop machine, which is also the machine where I got the other freezes. 
When I tried with my laptop, the page worked correctly (I'm not using the 
laptop much these days so I can't say whether Konqueror freezes on it too).

My desktop system as ha AMD Radeon RX 6700 XT graphic card: I've had it for 
several years and it has always worked flawlessly, so I think that if the cause 
is related to the driver, it's something new.

Given that Falkon is also showing this issue, I think the cause is not 
Konqueror itself but something else. I think I've found out when this issue 
started happening for me: between the last days of May and the first days of 
June. As soon as I have time, I'll try to look at the log of the packages I 
updated in those days to see  if there's something which could be related to 
this.

Stefano
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