PC suddenly or inexplicably won't recognize UEFI boot device(s)

Problem:  As title.  May show up on a machine that has been booting from USB for years.  USB media is working; no settings in BIOS help; moving the USB boot device to other USB ports doesn't help; rebuilding USB media doesn't help. 

A:  You might have plugged in a new USB hub, or other device, that is stopping your mainboard from finding the USB boot device.

I had this happen when I upgraded a little D-Link hub on my desk to a larger model with more ports.  Everything was fine in Windows, but on boot, this hub prevented my mainboard from detecting my USB boot drive.

It is indeed the hub, and not anything plugged into the hub.  I tried.

As a BIOS is relatively simple, I'm guessing the new hub (which is USB 3.0) is somehow incompatible with the BIOS detection protocol used to find UEFI boot devices.

As my mainboard is hardly current, this could be limited to just this hub, or maybe to all USB 3.0 hubs connected to older mainboards that don't support newer protocols.

I only use the USB drive to boot into a backup/recovery environment, so it wasn't a major thing.  But as a back up weekly, it is annoying, as I have to disconnect the new 3.0 hub in order to boot to backup mode.  I'll be trying another model.

Firefox not showing images or maps on certain websites only

Problem:  Firefox consistently refuses to load images on certain specific websites, which may or may not be image-heavy.  Examples may include Aliexpress or Google image search.

Firefox may also refuse to show map images on sites with map functionality, such as Kijiji / Craigslist and Samsung SmartThings Find, and news stories from the BBC, Propublica and others may be missing their images.  Images will just not show, or show placeholders; maps will show as "Sorry, we have no imagery here", or similar.

Other websites are consistently fine, and Chrome does not have any problems with the "bad" sites.  The usual fixes, such as clearing cache / cookies, don't work, limiting the problem to specific sites only.

Fix:  Firefox may be set to not load "webp" images, which are getting more and more popular.  The solution is here.

 I lived with this for almost 2 years and was beginning to think I'd have to switch to Chrome to get around it.  (I'm not a Firefox devotee, but I also don't like changing things around.)  I can't figure out why the webp loading setting was not enabled by default, or if it was, how it got switched off.

Google Calendar "Settings and sharing" says only "Settings" and not "Sharing"

 That is, the "sharing" options are completely missing.

I had 1 calendar of several like this.  I never could figure out how to fix it; I had to create a new one, move events from the broken one to the new one, and delete the broken one.

Yes, it's a pain, but there wasn't anything else for it.

Note that - depending on your calendar app - you may have to go into your phone Calendar app settings to make the new calendar actually visible!