Nothing here changes how the app behaves on a normal day. It repairs a safety
net that had quietly stopped working.
Getting connected needs credentials from VK, and there are two ways to get
them. The usual way needs no captcha and is what your app uses. If VK ever
closes it, the app falls back to solving a captcha by itself — and that
fallback had silently broken: VK rewrote the puzzle page, so the app could no
longer even read the puzzle, let alone answer it. It never reported this as a
format problem; it looked as though VK was refusing us.
It works again, verified on a phone: the app now solves those captchas on its
first try, without asking you to tap anything.
You will notice this only on the day the usual path stops working — which is
exactly the day you would not want to discover the backup was broken too.
Also fixed along the way: when a captcha could not be read, the log blamed VK
instead of saying the app could not read the page.
No server update is needed. srtp-build306 remains the current server release.