Tampermonkey causes net::ERR_FAILED for POST (JSON) requests on Twitter/Twitch ++ (v2.12 snapshot)

Pathduck

This started happening after the update to the last snapshot, based on Chromium 81.
Probably happens on other sites as well. This breaks major functionality on the sites making them unusable. Since I don't have an account on either site, can't confirm if also happens if user is logged in.

I've tried all the obvious stuff, private window, fresh profile, stable version, disabling all extensions. Works in all cases, and managed to nail it down to Tampermonkey being installed, even if not enabled for the site in question and with no scripts installed.

None of the obvious settings I've tried to change like the new content blocker, 3rd party cookies etc seem to affect this. I suspect something changed in Chromium 81 beta that somehow breaks stuff with Tampermonkey.

Responsibility for fixing this probably lies with the Tampermonkey devs, but it would be interesting to know what's changed in C81 that could cause this. If one of the V team could investigate as well it would be great

Reported as VB-64340 in case anyone's interested.

It's also reported on the Github for TM:
https://github.com/Tampermonkey/tampermonkey/issues/883

Net (only POST?) requests will fail with net::ERR_FAILED and the following headers:

Request URL: https://gql.twitch.tv/gql
Referrer Policy: no-referrer-when-downgrade

Provisional headers are shown
Accept-Language: en-GB
Client-Id: kimne78kx3ncx6brgo4mv6wki5h1ko
Content-Type: text/plain;charset=UTF-8
DNT: 1
Referer: https://www.twitch.tv/
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.41 Safari/537.36
X-Device-Id: 9ae71d0daaf1549e

[{operationName: "FrontPageNew_User", variables: {limit: 18}, extensions: {,…}},…]
0: {operationName: "FrontPageNew_User", variables: {limit: 18}, extensions: {,…}}
1: {operationName: "Prime_BlueBar_CurrentUser", variables: {,…}, extensions: {,…}}
2: {operationName: "Shelves",…}

LonM

@Pathduck There are plenty of extensions that this is happening with. Hopefully it will be fixed soon.

Pathduck

@LonM Thanks for the information. I noticed people were posting about Twitter/Twitdeck not working but no mention of Tampermonkey or what extensions. Is there a post listing extensions that break sites in C81?

Hadden89

@Pathduck The ones I know (workarounds may exist): ~~Ublock Origin, Nano Adblocker~~, Adguard, Privacy Badger, Pixiv toolkit, Tampermonkey, ~~Scriptjager~~, Umatrix and so on. ~~Most~~ Some extensions could trigger this specific bug.

//EDIT: Oh, that's interesting.
Yesterday I disabled extensions with the --disable-extensions on my single profile test install.
Today I've removed the switch and both twitch and twitter are working.

I can't be sure if it will work for Tampermonkey as I don't use it.

Guess some extensions data were corrupted on chr81 bump and the disable/enable status restored them.

iAN CooG

@Hadden89 said in Tampermonkey causes net::ERR_FAILED for POST (JSON) requests on Twitter/Twitch ++ (v2.12 snapshot):

Ublock Origin

I can't confirm, I am able to use uBO and twitch, twitter and reddit work as normal on both my Vivaldi profiles.
In my case, the only extension causing the problem on those sites, it Pixiv Toolkit 3.9.10, which I can keep disabled and enable only when visiting Pixiv site.
What I noticed is that I can disable it, go to Twitch and Twitter, and then re-enable it, both those sites continue to work until I close and restart Vivaldi

Hadden89

@iAN-CooG It was meant more as a "generic reported list".
Nice, so I guess even NanoAdblocker could be considered "bug safe" being a fork of Ubo.

iAN CooG

@Hadden89 the only way to know is to try and see by yourself if it's ok. I don't even know if some lists or custom filters used in uBO can cause the problem, but the ones I'm using seem to not causing any trouble.

Hadden89

@iAN-CooG For the moment everything is working. I just disabled all of them and re-enabled again. Snap seem to work fine.

Pathduck

So far the only one I seem to have issues with enabled is Tampermonkey. I have uBO, IDontCareAboutCookies, CookieAutodelete and SpatialNavigation (ext).

Disable and reenable works until the browser is restarted. I don't actually use Twitter/Twitch that much so for me not a massive deal. Hope it gets fixed soon.

But from what you guys are saying, this could potentially be fixed by the Vivaldi devs? I was assuming it was something in C81 that broke with some extensions. Possibly a lot of extensions need to be fixed because of this issue.

I just checked if the error I'm getting on Google Earth was related to this, but apparently not.

Hadden89

@Pathduck Not sure what could be.
Maybe a specific issue of the chromium 81 build used by vivaldi which can be fixed with the next minor chromium bump and/or some minor data corruption in the migration from 80.
Guess it'll be fixed soon (they usually test on chrome too and if it works there...)

Pathduck

@Hadden89 Yeah, apparently Chrome 81 will be out in a little over a week and they'll have a s**tstorm if it breaks stuff for so many extensions.

Can anyone using Chromium 81 beta check if the same applies there? I don't have it installed and not sure I'd want to

Streptococcus

Does ViolentMonkey cause the same problem? It is a workable alternative to TamperMonkey.

Pathduck

@Streptococcus That's a really good suggestion

I just tested, turns out Violentmonkey does not break sites like Tampermonkey. So thanks for that

Also tested with Tampermonkey Beta, since it's updated recently, but same error happens with it.
Violentmonkey was last updated 4/3 though so maybe they're more aware of the problem.

Tampermonkey has a lot of advanced security options, like stuff relating to Content Security Policy and HTTP headers, I wonder if some of those features are messing stuff up with C81...

Hadden89

@Pathduck said in Tampermonkey causes net::ERR_FAILED for POST (JSON) requests on Twitter/Twitch ++ (v2.12 snapshot):

stuff relating to Content Security Policy and HTTP headers, I wonder if some of those features are messing stuff up with C81...

It could be, they are testing the manifest V3 which do changes also on these feature, so must be some issue in the middle.

jumpsq

umatrix leads to the same results on twitter and some other sites, even if it's set to be disabled on the website.