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Comment by judge2020

8 hours ago

Yeah I don’t seem to feel any performance or functionality degradation myself. What <X> ad blocking related feature has been made impossible with MV3?

https://github.com/uBlockOrigin/uBOL-home/wiki/Frequently-as... has a few of the more practical concrete examples. Namely content can load without the blocker being ready to filter, CNAME cloaking can't be handled properly (in Chrom* at least), and the filter rules aren't as flexible.

Interestingly, the rule count limits themselves do not (currently) seem to be much an issue despite it being one of the more common concerns on the original MV3 announcement.

  • > content can load without the blocker being ready to filter

    This isn't an MV3 issue, it's a Chromium design decision that extensions cannot block browser initialization. It was also true with MV2. In fact, MV3 has improved the situation because DNR rules are enforced immediately.

    You could certainly argue that Chrome should allow extensions to block browser initialization, or that it should be user configurable - but it seems like an entirely defensible Chrome decision. Regardless, it's nothing to do with MV3.

    > the filter rules aren't as flexible.

    That's true, but they are still very flexible, and DNR makes some very nice features possible in uBO lite that were not possible in uBO.

    For example, did you know that you can change your User-Agent with uBO lite? Go to the Custom DNR rules tab, and enter something like this to pretend to be Lynx on whatever.com:

         id: 5
         priority: 100
         action:
           type: modifyHeaders
           requestHeaders:
             - header: User-Agent
               operation: set
               value: Lynx/2.9.2 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/3.5.7
         condition:
           requestDomains:
             - whatever.com
           resourceTypes:
             - main_frame
    

    I don't think that's possible in uBO, so clearly there are some benefits to switching. I have a ton of custom dnr rules, and love this feature.

    • Any MV3 issue could probably be summed up as "MV3 isn't so bad, just the implementation in Chrome" where Chrome defines MV3 (as it's not a W3C standard) and ships it as such.

      That said,

      > Chromium design decision that extensions cannot block browser initialization

      It's not "browser initialization" that was blocked, it was blocking network requests for pages until they were processed by all components in the chain. Notably, this could never apply applied to the browser or its internal pages itself.

      > It was also true with MV2.

      With MV2 you used the blocking version of https://developer.chrome.com/docs/extensions/reference/api/w... which no longer works with MV3 extensions in Chrome and then the request had to wait until it was given to and processed by the blocker.

      Firefox is a great example about all of the above points: MV3 still supports blockingWebRequest there, so it gets the best of both worlds.

      > did you know that you can change your User-Agent with uBO lite?

      With MV2 you'd use blocking webRequest and chrome.webRequest.onBeforeSendHenders. I'm not sure uBO ever bothered with this before uBO Lite, but it's a bit of a double standard to say "MV2 didn't offer blocking requests, that was a different API which happ

      3 replies →

Maybe or maybe not. But Youtube ads are now freely flowing through with MV3. That was the entire ruse.

The companies that don't want you using the lite version are waiting for full version to completely go away before blocking the lite one. No sense driving you to that. So, check back in a couple months and see if it's all still good.

I've seen some ads slip through the cracks nowadays, like I think Wikia ads for some TV shows I go to now have ads on them. They gave up on blocking Meta.

I believe the main things are that block lists have to be updated through the Chrome Web Store and there is an upper limit for things that can be blocked.

Severe limits on additional filters, which is bad for people who want it to add more annoyances than it does by default.