We need a browser project whose explicitly stated goal is to act as the user's agent. No, Mozilla's "open internet" nonsense doesn't cut it anymore. There's no point in an open internet if every web browser acts against its users.
Every decision taken by the browser developers should only keep in mind the requirements of the users. You want to play DRM content? Sure, we will get that certification but also provide extension APIs that let you save the stream to your disk.
You want to block ads? Sure we will let you load an extension that will do that. No store, no signing, no crap.
There used to be a saying, "You can't fix stupid". You can't protect a sufficiently motivated user from destructive action, you can only give them hints that what they are doing is probably unwise.
"Hey, it looks like this extension is doing inappropriate things with your passwords. Would you like to uninstall it?"
Users can reasonably expect an online password manager to exfiltrate their passwords, and if that's what they want they can install one.
The problem with the v2 manifest `chrome.tabs.executeScript` API is that it allows any extension that uses that API to become an undocumented password exfiltrator without any changes to the Chrome extension itself. The new API in manifest v3, in contrast, requires that if, say, my clock extension suddenly became a keylogger, the script that did that would show up in the extension.
The API change is to make it possible for Google to have any hope of vetting extensions in the Chrome Web Store by controlling how their behavior can mutate after Google has signed off on them for inclusion in the store.
Most people are not technology professionals and enthusiasts like this forum is. Should normal people be forced to put their life savings on the line because they didn't understand the difference between Manifest V2/V3?
... That browser is Chrome. Chrome's massive install base means it is the browser of choice for people who need a coddling browser.
Much as with Windows becoming the dominant operating system resulting in Microsoft having to deal with botnets fabricated from thousands of compromised machines via forced security updates, the dominant system becomes heavily incentivized to protect the least capable users from their own bad decisions.
Every decision taken by the browser developers should only keep in mind the requirements of the users. You want to play DRM content? Sure, we will get that certification but also provide extension APIs that let you save the stream to your disk.
You want to block ads? Sure we will let you load an extension that will do that. No store, no signing, no crap.