It's not a feature and you can't disable it, previously it'd just crash. I think it's to do with the content workers being `exec`d from disk each time instead of forking from a master.
I'll add the caveat that I typically restart my browser at least once a day, perhaps avoids the problem.
Later it stopped to crash, but acted weirdly (clicks on links didn't work, etc).
Nowadays we have the notice to restart the browser. It didn't arrive years ago, just a few releases ago.
This was only under Linux, and only with the distro package managers. Under Windows or MacOS, the updater updates the browser on next restart, so this didn't happen.