Ich hab meins Dampfterrasse genannt

Ah, now I got what you meant. I was just suggesting switching temporarily while the published 0-day would be public and unpatched, because this is the time in which the issue would be exploited the most.

Of course there are unreleased 0-days, but you can't do anything about it. Most of them are even kept secret by companies that sell spy software. However, public 0-days are way more dangerous because they are being exploited actively.

Using a different browser until a particular issue is fixed when you are e.g. a journalist still helps with getting hacked.

I wonder why they suddenly decided to cave in.

IMO, as long as you keep doing it every day, there is not really a bad way to learn anything.