Thank you for tracking root cause and reporting it.

The 'community' link at the bottom of the page is also dead :

Could you point exact location? I checked the page and sources and there is no mention of either tigase.tech or tigase-ios-messenger

Ok so I did a few tests and wrote a lot of stuff that I'm leaving under here for the record, but I should have started with the obvious test :

https://downforeveryoneorjustme.com/tigase.tech

shows tigase.tech is down. So this one may not be related to any blocking.

Old Message (probably irrelevant now) :

I assumed it was in there, but I'm not sure anymore... I still can't access tigase.tech, although dig shows some records :

$  curl tigase.tech
curl: (6) Could not resolve host: tigase.tech

$ ping tigase.tech
ping: tigase.tech: No address associated with hostname

$ dig tigase.tech @8.8.8.8

; <<>> DiG 9.16.22-Debian <<>> tigase.tech @8.8.8.8
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 28536
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;tigase.tech.			IN	A

;; AUTHORITY SECTION:
tigase.tech.		900	IN	SOA	ns-1478.awsdns-56.org. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400

;; Query time: 59 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Mar 09 12:04:57 CET 2022
;; MSG SIZE  rcvd: 125

I can access other *.tech sites (e.g : https://get.tech/ ) , so I'm ruling out *.tech blocking in my DNS setup. I tried with several different public IP/providers, various DNS and devices, and still no access to tigase.tech.

'tigase.tech' is old domain, I changed the community link to point to github

Great, this settles that then. Feel free to close the issue as there's not much more that can be done on your side for de-listing tigase.net I guess. Thanks for your time and answers !