Created attachment 211777 [details]
Screenshot of the problem

You mean the currently selected item in the file list is not highlighted?

Isn't that a gtk+ or style bug?

Yes to first question, I've been seeing this too. Totem doesn't have this issue

Could be something in our custom CSS, but i don't see anything suspicious.

Can no longer duplicate with:

Installed Packages
Name        : gnome-boxes
Arch        : x86_64
Version     : 3.4.3
Release     : 1.fc17

Thanks Stef for reporting and then verifying!

There's a bug in gnome-boxes 3.4.3 causing the css not to be loaded and the media list to look ugly:
(gnome-boxes:32521): Boxes-WARNING **: main.vala:88: gtk-style.css:105:18: Horizontal and vertical offsets are required
Once you remove lines 105 and 106 from this file, boxes is back to its usual looks, and the selection in the file open dialog is broken.
This is reproducible with git master as well.

Created attachment 217028 [details]
non working css to the left, working css to the right (to understand what I'm talking about)

This 'bad look' has been verified on a non development fedora box, and the file chooser selection is missing there

(In reply to comment #8)
> Created an attachment (id=217028) [details]
> non working css to the left, working css to the right (to understand what I'm
> talking about)
> 
> This 'bad look' has been verified on a non development fedora box, and the file
> chooser selection is missing there

That seems to be a  different bug. Why reopen this one?

(In reply to comment #9)
> (In reply to comment #8)
> > Created an attachment (id=217028) [details] [details]
> > non working css to the left, working css to the right (to understand what I'm
> > talking about)
> > 
> > This 'bad look' has been verified on a non development fedora box, and the file
> > chooser selection is missing there
> 
> That seems to be a  different bug. Why reopen this one?

Because this bug is about "cannot see selection in file open dialog" and this bug would still happen in the 3.4.3 f17 package if there was not this other bug, and this still happens in git master as well?

(In reply to comment #10)
> (In reply to comment #9)
> > (In reply to comment #8)
> > > Created an attachment (id=217028) [details] [details] [details]
> > > non working css to the left, working css to the right (to understand what I'm
> > > talking about)
> > > 
> > > This 'bad look' has been verified on a non development fedora box, and the file
> > > chooser selection is missing there
> > 
> > That seems to be a  different bug. Why reopen this one?
> 
> Because this bug is about "cannot see selection in file open dialog" and this
> bug would still happen in the 3.4.3 f17 package

I'm now even more confused. Stef reported that he can't reproduce the issue in exactly that version/package and you are saying that its still reproducible.

The 3.4.3 package has a bug, at least on the machines I've tested it on, which hides this fileselection bug.
We'll need confirmation from Stef if he hits the issue I've described, which is why I've attached a good/bad screenshot.

This is caused by "background-color: transparent;" in

.view,
GtkClutterOffscreen,
.boxes-bg {
    background-color: transparent;
    background-image: none;
}

I'm CSS-illiterate so no idea what a fix would be

(In reply to comment #13)
> This is caused by "background-color: transparent;" in
> 
> .view,
> GtkClutterOffscreen,
> .boxes-bg {
>     background-color: transparent;
>     background-image: none;
> }
> 
> I'm CSS-illiterate so no idea what a fix would be

good time to learn some bits :)

afaik, .view is the class used for list/tree view, so we need to check what really need this, you can try removing .view line perhaps and see :)

(In reply to comment #14)

> afaik, .view is the class used for list/tree view, so we need to check what
> really need this, you can try removing .view line perhaps and see :)

Yep, this helps too.

Yeah, using something as wide as ".view" here seems pretty risky anyway. We should remove that, and if there is some problem with that we should add a more detailed rule to only fix that problem.

Created attachment 217535 [details] [review]
Fix not showing selection in file selector

We were using a way-to-broad CSS selector like ".view" which
also affected the file selector. Remove this and instead apply
the (already also matched) boxes-bg style class on the .view
places that needed to match.

Attachment 217535 [details] pushed as e5eccfa - Fix not showing selection in file selector