The default startup reads the users configuration, that is the condition that needs to work without options.
The idea is to check whenever a "portable" file exists within the main exe install path before reading the actual `geany.conf` file. If it exists, it should overwrite `app->configdir` and **then** read `geany.conf`.
As alternative, [avidemux and other programs simply check if the main exe was renamed as "avidemux_portable.exe"](https://github.com/mean00/avidemux2/blob/291b7d7aab70b7457a743e96e803f9fa071...).
be aware it is only forward compatible, ie we always try to make newer Geany versions read what older versions wrote, but can't guarantee older Geany versions will read what newer ones write.
no problem with that limitation.