Firefox developer tools console and network tabs broken

[Guido Falsi]

On 24/06/20 14:24, Jan Beich wrote:
> Guido Falsi via freebsd-gecko <freebsd-gecko at freebsd.org> writes:
> 
>> Hello,
>>
>> Lately I've noticed some problem on my machine with recent firefox.
>>
>> In the developer tools the network tab stopped working some updates ago.
>> I started using the console tab with request tracking there in it's place.
> 
> Network tab seems to work fine in Firefox 78 inside a fresh 11.3 i386 jail.
> 
>> Now the console tab stopped working too, if I open that it is just blank
>> inside.
> 
> Also works fine here.
> 

First thanks for the quick reply.

Thanks to your suggestions I found the problem (see below)

>> I am also seeing similar behaviour with the quarterly package and in a
>> manjaro linux VM. On windows it seems to work fine though. SO it does
>> not look as a porting issue. Is this known or being worked on upstream?
> 
> On Linux try using mozregression to track down the cause. After that you
> can check if anyone else has filed a regression bug or try to reason why
> your configuration broke.
> 
>> Some google searches gave me no results.
> 
> Does it affect new profiles as well? Try
> 
>  $ firefox --new-instance --profile $(mktemp -dt ffprofile)
> 
> Do you see any errors on startup? Try
> 
>  $ firefox --jsconsole
> 

This one let me find the issue, I got:

console.error: (new ReferenceError("IntersectionObserver is not
defined",
"resource://devtools/client/webconsole/components/Output/ConsoleOutput.js",
93))


and in fact I had this in prefs.js:

user_pref("dom.IntersectionObserver.enabled", false);

Can't remember why that was there, maybe some old test that lingered there.

It looks fixed now, so many thanks and sorry for the noise!

-- 
Guido Falsi <mad at madpilot.net>