Go to a forum with embedded tweets. Set ETP to strict, and they won't show up.
Funnily enough, embedded tweets have been broken for me for a long time. However, that's because I route all my Twitter needs through
Nitter via LibRedirect and the Nitter embeds just never work at all. I'll take your word for it on that one.
Go to GRC cookie forensics, and the browser will fail the test. Set ETP to custom and block third-party cookies and it'll pass.
This one is a bit contentious for me, because I feel like Strict ETP will always fail this type of test no matter what. The test specifically checks for whether all third party
cookies are disabled
in the browser. Strict ETP now makes use of
Network Partitioning which goes beyond the scope of cookies itself. Network Partitioning itself is an implementation of
Client-side Storage Partitioning, a standard being developed by the
W3C's Privacy Community Group.
At a TLDR level, Network Partitioning separates caches and storage mechanisms for things like fonts, cookies, images, CSS, among other such things. Exceptions, however,
must be made for certain cross-site cookies for functions such as login, authentication, and the like.
Official Mozilla user documentation does acknowledge that Strict ETP doesn't block all third party cookies. That's why the setting for third party cookies is still enabled, and that's why it fails the test.
It must be noted that Network Partitioning
can be broken by persistent cookies depending on what kind of exceptions are made. Depending on how severe your paranoia meter is reading, blocking all third party cookies may be preferable. In my case, Strict ETP
seems like a more elegant solution so that's what I'm sticking with.
Automated tools are pointless because it'll only take you a few minutes to make changes in configurations and about

onfig. I tried LibreWolf, Arkenfox, etc., and they broke some sites.
I feel like you're being a bit dismissive here. I've sperged a lot about LibreWolf in past threads, so I won't comment about it here. As for Arkenfox, I don't wanna sound like an elitist, but that's the kind of outlook people have if they don't actually
read the fine manual from start to finish. Arkenfox, by design,
will break things. The onus is on the user to create a
user-overrides.js
file with the specific modifications they want, and then execute the updater/prefsCleaner scripts to commit the changes. No one is expected to run Arkenfox on default settings, and it's highly discouraged.
It sounds autistic as hell, and to be fair, it is.
BUT the scripts are foolproof to a certain degree. Your user.js is backed up, as are your prefs.js, making it easy to roll back undesirable changes. Similarly, the syntax for user overrides is quite easy to get the hang of (if you're autistic like I am and actually like mucking about with text files). It's not even
that complicated to get started.
Code:
user_pref("$EXACT_firefox_about:config_setting_goes_here", $value_like_true_or_false_or_1_or_2_or_"URL"_or_whatever);
Now imagine this: you have all your
about:config
flags arranged all neat and pretty in a little file, an updater script that commits your changes, and a cleanup script that makes sure nothing borks your installation. That's how Arkenfox runs. I have Arkenfox running right now, and I make good use of WebGL, DRM, and URL searching (which are all disabled by default) while still making use of its benefits. To be fair,
FFProfile accomplishes a similar effect, but I lean toward Arkenfox because the updater/cleanup scripts
really make troubleshooting that much easier for me. Again, your mileage may vary so maybe I am being an autistic fuck here.
uBlock Origin or Adguard in default mode is not more than adequate because some annoyances in sites will still show up. You have to block them manually.
My mind completely blanked there. I meant to say "uBlock Origin in default mode with NoScript doing the rest." That's been my configuration for a little while (i.e. the last 30-45 days). Sorry about that
Multi-Account Containers are helpful if you have several accounts for various sites or if you have to turn off ETP for reasons given earlier.
No disagreements there.