I’m running MX Linux. Just downloaded Neochat through MX’s package installer/Flatpack.
Neochat accepts Matrix ID for login, proceeds to password screen. I input password, Neochat processes it for a moment, then crashes.
Please report crashes using https://bugs.kde.org after reading Get Involved/Issue Reporting - KDE Community Wiki. Make sure your bug report includes a backtrace with debug symbols, or else it won’t be actionable. To learn how to do that, see Guidelines and HOWTOs/Debugging/How to create useful crash reports - KDE Community Wiki.