I thought that incognito mode in Chrome[0] and private mode in Firefox[1] already disables extensions by default.

[0] https://support.google.com/chrome_webstore/answer/2664769?hl...

[1] https://support.mozilla.org/en-US/kb/extensions-private-brow...

Absolutely, except for extensions you explicitly want to have in private mode, which is opt-in.

So? Extensions are opt-in in regular mode too.

I'm agreeing with my parent comment, to which I'm adding some precision.