A few new experiments:
1. `firefox --headless` stays quite no matter what
2. when `gimp` is running, `context --help` causes a rise of cpu usage of
gimp up to 60% for ~1s
3. when only xfce4-terminal is running, I tried `context --help` for a few
times and for each time, one of the following experiences a cpu usage rise
up to >50% for ~1s:

libwhispermenu.so
libpulseaudio.so
xfce4-appfinder
nm-applet
Thunar
xfce4-terminal

On Fri, 30 Oct 2020 at 10:07, Taco Hoekwater <taco@elvenkind.com> wrote:

>
>
> > On 30 Oct 2020, at 09:34, ntg@scorecrow.com wrote:
> >
> > Hi Sylvain,
> >
> > This bug tracker report <
> https://bugzilla.mozilla.org/show_bug.cgi?id=1599329> describes lagging /
> freezing (which are symptoms of excessive CPU usage, of course) for
> versions of Firefox from 70 to 74 inclusive on Manjaro. They also report
> Chromium seeing the same problem.
>
> This basically says it is a bug in the video driver.
>
> You could test that theory by switching to a text terminal for running the
> ‘context’ command (assuming the text-only terminal is still accessible in
> Manjaro) and see whether the output of ‘context —help’ causes lag there as
> well. Even a really, really crappy video driver should be able to handle
> the output stream in full-screen text mode, so if it still lags in that
> environment, that moves the needle toward a problem in ConTeXt (however
> unlikely Hans and I think that is).
>
> Best wishes,
> Taco
>
> ___________________________________________________________________________________
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>