A. None of the dark schemes (bright text) view well with the current editing line which has a bright background highlighter. Am I missing something ?
B. The editor frame doesn't change color (as explained in another closed issue) because it is part of the GTK themes. But it does change if you ask Geany to invert ALL colors. In such a case, should not dark theme developers design their themes for inverted mode instead of normal mode?
A. both the translucency and colours of the current line can be set by the theme, so I guess its up to the theme makers how they want to show it.
B. not sure exactly what you mean by "frame" but it what I would call the frame doesn't change colour with "invert colours" for me.
A. My bad. I found out that the current line colors were over-ridden by filetypes.common. Commenting them out fixed this.
B. By 'frame' I really meant the line numbers on the left hand side. Colours will change when in 'invert syntax highlighting colours' is on. (linux lubuntu 18.04, Geany 1.32).
Ok, what you are calling "frame" are the "margins". The "frame" is a GTK thing around the editing widget and is set by GTK themes. "Margins" are part of the editing widget and are set by "colour schemes" as in this repo. (Maybe "themes" is a bad name for the repo, but thats what it was initially called and thats what its stayed).
The editing widget is not affected by GTK themes since its unrealistic to expect global desktop themes to set values for things like "line_numbers" or "folding" or "C program types" etc, and so the Geany "colour schemes" fill that gap.
But it appears complicated.
`filetypes.common` (overridden by user `filetypes.common`) sets common styling settings.
`filetypes.XXX` sets filetype dependent styling settings for filetype XXX (also overridden by a user version), mostly the styles for syntactic elements of the filetype.
Each setting can be set to a value or a named style.
`filetypes.common` also has a default set of values for the named styles.
The values of the named styles are set by the "colour schemes" if they want to change the default.
So if a setting in `filetypes.common` or `filetypes.XXX` is set to a named style it can be set by the colour scheme, but if its a value the colour scheme can't change it.
For example translucency values are set to values in `filetypes.common` because on some very olde platforms changing them would crash Geany so it was better they were not fiddled with by colour schemes which are platform independent, but values are overridable by user `filetypes.common` (on the doubtful assumption the user knew what platform they were on :-).
This way colour schemes do not have to set values for each syntactic element for each programming language, just a common set of named styles and the `filetypes.*` files map them to actual common or programming language settings.
I use dark mode Ubuntu and i can't read the first line in Geany's "Messages" pane. When this pane displays search results, this first line is dark blue on black background and there is no contrast at all. I've tried various dark geany's themes but none of them changes this first line color. How can i have a light color for this first line text ?
See blue line on screenshot : 
@JLuc Geany themes/colour schemes only apply to the editing widget, not other UI elements.
Great editing geany.css could fix it cf https://github.com/geany/geany/issues/2644#issuecomment-1115861043
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