Unpredictable website issues on ancient hardware

[jms2]

This is totally off topic, but I'm posting on here because I know the readership is very well informed and helpful. It's very much not a criticism of the Stardot website, but Stardot is good example of the kind of website that is affected by the problem I'm experiencing.

So... I have a very old Android tablet (it's from 2012 and runs Android 4.2.2). I'm using Chrome as the browser. Although it's obviously ancient and rubbish, it actually performs OK for the very limited thing I use it for, which is typically browsing Stardot and the BBC website for 5 minutes while trying to wake up in the morning, or running a crossword solver app. Or at least it did, until a couple of weeks ago.

The problem I'm seeing is that for all but the biggest websites, it blocks access due to security concerns. This might be understandable, because admittedly the system is really old, but the bizarre thing is that the behaviour is completely unpredictable and varies from one day to the next.

"Big" websites like Google, the BBC, Ebay etc are completely unaffected. Pretty much every other website gets blocked (err_certificate_invalid), but with varying effects:

- Initially, there was a button I could press to ignore the security issue and proceed anyway. This wasn't too big a deal.
- Then, after a few days, it started forcing me to press the button for every single page within a site, rather than just once.
- Another behaviour is just not letting me in at all, saying that the site uses something called "HSTS", which I have never heard of.
- Deleting cookies etc sometimes fixes it, for a day or so. Then after a while it goes back to one of the above.
- I deleted Chrome, which was a really old version and which said it couldn't update, and re-installed it. The new version does indeed seem new, and this fixed the problem. But only for a couple of days.

The inconsistency just doesn't make any sense to me at all. I'm quite prepared to buy a new tablet if necessary, but can anyone explain what is happening in a simple way?

[lushprojects]

It sounds like it might be due to changes to the certificate structure used by LetsEncrypt which seems to be causing particular problems with old verisons of Android:
https://community.letsencrypt.org/t/mis ... e/214877/3

I would guess that the websites with problems are using LetsEncrypt.