Accessibility: focused widgets not visually distinguishable

[vvillenave]

Expected behaviour

When using keyboard navigation, it’s paramount that one can tell
where the focus currently is. Many of the provided themes do not
currently allow that.

Actual behaviour

Let’s play “where’s the focus”. I’ve provided two test cases: one
with a minimal GtkStackSwitcher interface, the other one with a
real-world example (in this case Inkscape).

In the first example, the page opened is obviously the first one
(numbered 0), but the keyboard focus is actually on the second
tab button.

	BlackMate
	BlueMenta
	BlueSubmarine
	GreenLaguna
	GreenSubmarine
	HighContrast
	HighContrastInverted
	Menta
	TraditionalGreen
	TraditionalOK

The second example is with a real-world application (in this case, Inkscape):
here the focus is actually on the second combobox dropdown button “mm”,
in the “Custom size” section. (You could be led to believe that it’s in the
previous entry field “Height”, but it’s not.)

	BlackMate
	BlueMenta
	BlueSubmarine
	GreenLaguna
	GreenSubmarine
	HighContrast
	HighContrastInverted
	Menta
	TraditionalGreen
	TraditionalOK

As you can see, the only theme that scores well in both cases is really
HighContrast (even HighContrastInverted fails in the second round.)
BlueMenta is also actually fairly usable; as for the Submarines, they
have no notion of any focus whatsoever.

Steps to reproduce the behaviour

If you want to play at home:

• download the minimal GtkStack example I provided,

• launch it using glade-previewer,

• hit the Right arrow twice to reach the second tab
  (if you’re not sure as to said focus actually moved, hit Space to confirm).

• Next up, fire up Inkscape,

• open the Document properties dialog (Ctrl-Shift-D),

• Hit Tab seven times to reach the second combo box.

MATE general version

Reproduced with both 1.20 and master.

[raveit65]

Submarine themes has focus , see the thin green line on open(öffnen) button.

[vvillenave]

Submarine themes has focus , see the thin green line on open(öffnen) button.

Indeed; that was a bit unfair of me. But the equivalent CSS selector for
combo boxes, Tab buttons (and possibly a few other things) seems to be missing.

[raveit65]

combo boxes, Tab buttons (and possibly a few other things) seems to be missing.

Nope, everything is there. Same status like Menta themes.
eg. Notebook tabs (dotted line).

Please test carefully, i am not willing to post more proofs ;)

[vvillenave]

Nope, everything is there. Same status like Menta themes. eg. Notebook tabs (dotted line).

Thanks for investigating; indeed there are some focus cues, but I wouldn't call that "everything" :-)
Your example is striking: Tab buttons in a GtkNotebook do have some focus selector; however in a GtkStack, less so.