Specify which file types show in the Open File dialog in CodeLobster IDE

I have an HTML editor (CodeLobster IDE) and when I do ‘open file’ a whole gamut of file types appear in the file box – including jpg, gif, and several others. Not sure why it thinks I want to edit a picture using an HTML editor.

I want the default file type to be .htm(l) – is there any way to set this, say in the registry? Ironically I know how to do this programmatically but of course the CodeLobster app is already compiled and installed.

Not a huge issue but it would be nice if I could do that. It’s a bit like file association but in reverse.