I got Lightning donations working as again on the https://alice.btc.calendar.opentimestamps.org/ and https://bob.btc.calendar.opentimestamps.org/ OpenTimestamps calendars.

If you'd like to donate, go to either of those URLs and use the Lightning invoice on the page. That's much appreciated, as tx fees and VPS servers all cost me money.

...the only catch is the way those invoices are implemented is hilariously shoddy: I have a watch job that makes a new LN invoice every few seconds. And I turned on garbage collection of expired invoices¹ in my lnd configuration. So there is a small chance that you'll get an invoice that was shown to someone else already.

I didn't want to generate a new invoice on every visit, as I'd need to figure out how to properly rate limit it so as to not open up a DoS attack. In practice people don't donate anywhere near frequently enough for this to matter. So good enough for now.

1) gc-cancelled-invoices-on-the-fly=true