(In reply to Alessandro Castellani (:aleca) from bug 1586264 comment #3)

Everything works perfectly for both XMPP and IRC accounts.
I don't know if you're aware, but I got a bunch of console errors while
using it.
I didn't notice any issue in the client, tho.

JavaScript error:
file:///home/alecaddd/Mozilla/source/obj-x86_64-pc-linux-gnu/dist/bin/
components/imIncomingServer.js, line 163: TypeError: this.imAccount is null
JavaScript error: chrome://chat/content/conversation-browser.js, line 425:
TypeError: this.docShell is null
prpl-irc: Failed to set character set to: false for aleca@irc.mozilla.org.
JavaScript error:
file:///home/alecaddd/Mozilla/source/obj-x86_64-pc-linux-gnu/dist/bin/
components/imIncomingServer.js, line 163: TypeError: this.imAccount is null
prpl-irc: Failed to convert CAP LS
 from Unicode to false.
prpl-irc: Failed to convert NICK aleca
 from Unicode to false.
prpl-irc: Failed to convert USER Thunderbird 0 * aleca
 from Unicode to false.
prpl-irc: Failed to convert CAP REQ multi-prefix
 from Unicode to false.
prpl-irc: Failed to convert NICK aleca1
 from Unicode to false.
prpl-irc: Failed to convert CAP END
 from Unicode to false.
prpl-irc: Failed to convert PROTOCTL NAMESX
 from Unicode to false.
prpl-irc: Failed to convert WATCH C
 from Unicode to false.
prpl-irc: Failed to convert JOIN #test
 from Unicode to false.
prpl-irc: Failed to convert MODE #test
 from Unicode to false.
prpl-irc: Failed to convert PRIVMSG #test asd
 from Unicode to false.
prpl-irc: Failed to convert WHOIS aleca
 from Unicode to false.
prpl-irc: Failed to convert WHOIS aleca
 from Unicode to false.
prpl-irc: Failed to convert WHOIS aleca1
 from Unicode to false.

Thanks for opening this

I was unable to reproduce this when doing a clean build off of tip of c-c and m-c. Is there anything special with your account? What network were you connect to?

It happens when I connect to irc.mozilla.org.
This errors appear when I open the Accounts Dialog and I click connect on my IRC account. I set it to not connect on start-up.
I'm too on a clean build off of tip of c-c and m-c.

Alessandro, can you go to your account properties and see if the the "Character Set" has a value of "False"?

After reading more into it, I'm fairly certain this is a duplicate of bug 1591148.