Opentopomaps missing since last update?

[landogar]

I really like the Opentopomaps but for some reason they were removed recently? Actually, I can't find any maps anymore.

How can I add Opentopomaps back?

[Tronpo]

Hello the default file onlinemapsurces.xml, it has the opentopomap map.

[LaurentG]

Which version of Android is your phone ?

I ask the question, because if you are under Android 7 (or older), this is a general problem in accessing https web sites with certificate provided by Let's Encrypt, that is no more possible with old android smartphone, since beginning of this month.
It remains possible to browse them with Firefox, but not with any other browser, nor any app.
(search "letsencrypt android 7" on google to get details)