A plugin is a way to run any code you'd like within The Blind Date Game. As such, The Blind Date Game's devs do not provide support or plugin related mods. If you have any questions regarding plugins (or any mods, really), the modding channel of the discord server is the best place to ask.
Since you can run any code you'd like through this, you're expected to have some basic knowledge relating to code and how Godot as a game engine works. The Blind Date Game isn't currently open source (though I may publish the code in the future), so some experimenting may be required to get specific behavior.
Below is a very basic tutorial for creating a plugin mod:
Navigate to “AppData\Roaming\Godot\app_userdata\Blind Date Generator\Mods\Plugins” and create a folder for a mod.
Within the root of your folder, you will need a ".tscn" file.
Any ".tscn" files in the root of your mod's folder will be loaded once the plugin is enabled, so if you don't want a file loaded, place it in a subfolder.
For this example, I've made a mod that spawns a white ColorRect node in the center of the screen and runs code to modulate the color.
3. Once your ".tscn" is in your plugin folder, you'll need to make sure it knows where it's assets are.
For the example mod, my code file needs a new file path.
You'll want to do this for any file in your plugin that has an external resource file. Textures, scripts, Godot scenes, etc.
use "user://" instead of the full mod folder filepath to keep your mod easy to share.
4. Now, in game, you should get a warning when you go to load mods. This means that The Blind Date Game has detected a plugin mod and is asking permission to run it.
Click "Enable Plugins" to see if your mod works.
Riveting.
5. Assuming nothing crashed, your mod should be working! Congrats!
At this stage, you can program more advanced features for your mod or send it off as a .zip to be extracted in other people's "\Plugins" folder.
Good luck making mods!