Yes, but if you write your own extension maybe you want to read and modify the data. For example, patch fingerprinting script so that it gets the wrong result.
Furthermore, malicious extension can read the data from the DOM, from forms (for example, password or credit card fields), and in some cases, from JS variables. They can insert fake information into the page. So preventing extensions from reading network data still leaves a lot of options for a malicious extension.
So you're saying that because Google didn't completely up-end the security model and break almost every extension in the one-go, we should have no-progress towards a more secure extension model?
uBlock Origin via declarative blocks is almost as powerful as the original. While I would trust gorhill with almost unfettered control over my browser, I don't trust EVERY extension owner (no do I trust uBlock Origin in perpetuity).
>So you're saying that because Google didn't completely up-end the security model and break almost every extension in the one-go, we should have no-progress towards a more secure extension model?
A funny argument to make because the thing that would make such a measure ridiculous as you rightly point out, is exactly what already makes the Manifest changes ridiculous in the first instance. They were making a rhetorical point and you elaborated on their point for them as if doing so expressed a disagreement.
I think a big step forward, towards a better security model, was overall a good thing, even if it meant that a good extension no longer had unfettered access to everything your browser saw. I don't think this change is ridiculous at all. And I don't want them to stop here either! v4 should close more of the avenues that malicious extensions are abusing! Extensions should declare everything up-front, so it's easy see if abuse is occuring.
How do you secure against the system vendor (in this case the browser) limiting what the consumer/user can or can't do (alone or with the help of third parties) with the product after acquiring it though? After all security for individuals against commercial and otherwise organized interests is one of the, if not the most important security after life and health. Even if one values the market overall for financial reasons, there is a solid argument that preventing modifications (and thus also repairs) is anti-competitive. It would be damaging to society if manifestV4 is realized restricting what can run further, much like printers and operating systems where the users ability to run software they bring themselves is limited has been. Just as no one should have to go to a mechanic with a special deal with the manufacturer to get their car or tractor to work as desired, neither should users of software.
You use a different browser, like Firefox.