At office there's an Asterisk VoIP server. Windows users use either Zoiper or 3CX clients. But I was wondering if there's a known free open client for Leap (or Linux in general).

Before you mention it, neither Ekiga nor Empathy (which seemingly replaced the former or something like that) are very convincent for me due to this, this and this (1st and 3rd ones I didn't consider them precisely as "solved" by the way...)

After a quick search I found a short list of free clients ; among Linux ones all seem to be either very slowly developed (latest stable dating more than a year ago) or no longer at all (several years since latest stable). Even so, some of the most mentioned ones around internet seem to be Twinkle and Linphone.

Do you know about a good SIP client you could advise for?