With firefox themes enabled, when you hover over or click a toolbar button, the background of the button is from the OS theme and not the firefox theme. https://wiki.documentfoundation.org/File:Toolbartheme.png
Do you mean the background colours of the tooltips?
In the image link, if you look at the non-printing character icon, which is pressed, it doesnt have the firefox theme shown in it, it is showing the theme which would be there when there isnt any firefox theme applied. You can see similar theme problems with the style, font name and font size drop downs.
Ok, but in this case it looks a little bit different in my case with LO 4.3.2.2 Win 8.1, because here they are blue and not grey. With blue selected buttons it is not that striking as with grey. But the drop-down list boxes are also grey. All in all, it would be nice if the buttons/boxes would fit good to the selected theme.
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