[APP BUG] Inconsistent default and user configuration files

Please confirm the following points:

• This report is NOT about the Android apps in the Play Store
• I have searched the project page to check if the issue was already reported

Affected Application

projectM Standalone SDL2 Frontend (includes the Steam app)

Affected Version

2.0-linux-pre2

Operating System

Linux (Desktop)

Additional Application Details

https://github.com/kblaschke/frontend-sdl2/releases/download/2.0-linux-pre2/projectMSDL-2.0.0-Linux-x86_64.deb

Type of Defect

Other

Log Output

Describe the Issue

The default configuration file installed with the package and the auto-generated user settings file use different syntax and setting names, for example:

/usr/share/projectMSDL/projectMSDL.properties

window.fullscreen.exclusiveMode = true
window.fullscreen.width = 0

~/.config/projectM/projectMSDL.properties

window.fullscreen.exclusive: true
fullscreen.width: 1220

The setting window.fullscreen.exclusive doesn't even work and needs to be changed to window.fullscreen.exclusiveMode manually.

Folder names are also inconsistent (projectM vs. projectMSDL).

Additionally, the settings dialog in the frontend doesn't reflect the current settings of the default configuration file.

Compare /usr/share/projectMSDL/projectMSDL.properties with ~/.config/projectM/projectMSDL.properties, including the setting names and folder names shown in the report. Start by tracing how the standalone SDL2 frontend reads these files and how its settings dialog reflects them. Done means the packaged defaults, generated user settings, and dialog use consistent names, paths, and syntax, with fullscreen settings working.