Hi all! Blender newbie here !
But definitely not new enough that this should be a problem, confused!
All of a sudden I’m unable to select a face in edit mode (or a vertice). If I press A to select all it will do it (though it seems to only select vertices not the faces), but individually clicking a face won’t… I’ve quit Blender and also restarted my computer. So confused!
Hi,
You mean that when you do LMB on an individual face it doesn’t select while in edit mode?
Yes exactly. Even the cursor doesn’t change, it’s still a crosshair. Oh I just figured it out. The ‘Toggle X-ray’ button somehow was clicked… !!! Ugh. That took forever to figure out. Thanks anyway, appreciate you taking the time.
Glad you solved it. 
Hmm… but still this should work even with X-ray-toggle…
One thing i noticed in your screen-shot… for this status bar options you have to hold Ctrl… so… does your keybord play tricks one you ??
In Xray mode you have to click relatively close to the little black dot in the middle of the face, if you click the face too far away from it it does not select.
Well… i mostly select my face not this far away… so i may have never noticed that… 
beware of the hidden joke 
It is one of those things we do unconsciously, without thinking about it. It behaves like that because in xray mode you can select faces behind other faces so Blender has to distinguish somehow which face you want to select.
