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V4.103(SVN#7769) does not save working INI files.
Tera Term doesn't save user setting automatically. To save setup, "Setup"-"Save setup" manually.
serial port is greyed out as an option.
When Tera Term is connected other than serial port, user cannot change serial port setting.
Both are features, not bug.
Tera Term
V4.103(SVN#7769) does not save working INI files. Such files do not contain any user settings. When invoked they merely start a vanilla session. When they are invoked, serial port is greyed out as an option. So the INI concept is unusable for users of serial ports or for those wanting to customise settings. Settings that are lost/not saved include connection type & settings, terminal settings, window settings.
Teraterm is running on Windows 10 Pro version 1803, build 17134.915 .