Greybeard

Have the camera ready in shooting mode (musn't be set to video as that is a separate Q menu). Long press the Q menu button until the menu comes up in edit mode. Use the joystick to position the cursor over each item you want to change and press the joystick (you will see the menu of Q menu items and be able to scroll and change to the one you want) When you have the Q menu looking the way you want use the Disp Back button to return to shooting mode. The Q menu should now be changed.

Never seen this happen - next time try accessing the card as though it was a file system (using whatever the Mac file explorer program is) - if the camera can see them then they must be there

Yes - you are restricted to 4:2:0 internally (and can't shoot at 400Mbps)

That information is in the EXIF data - you can try this viewer - make sure to click on a RAF or JPG file straight out of the camera - some software (such as Lightroom or maybe ON1) deletes the Fuji specific metadata: Fujifilm EXIF Viewer

I was just in the middle of replying to your first post to point out that it isn't quite that simple with Fuji - even if you use AF-ON you still need to choose a focus mode. You can use AF-M in combination with AF-ON - as long as you keep your finger on the AF-ON button it will keep focussing and stop when you take it off (provided you have chosen AF-C for instant AF mode) - but its not the same as using AF-C.

I am currently using Lightroom to process raw files from the X-S10. I'm not sure Fuji jpegs are dramatically different from other jpegs - you obviously have less scope for changes compared to raw files and its more important to get things right the first time. You could look at the Dynamic Range and D Range Priority settings in the IQ menu to help avoid blowing our highlights in jpegs.

Yes you can - here is the manual section that describes the functions that can be assigned to buttons: http://fujifilm-dsc.com/en/manual/x-s10/shortcuts/function_buttons/

"In my Nikon the menu returns to where ever I was last." I believe the FujiFilm rules go as follows: - if you have MyMenu items it always goes to the first of these - if you don't have MyMenu items then it goes to the first item in the IQ menu when you first turn the camera on - once the camera is turned on (and there are no MyMenu items) it goes back to the last item selected so long as that item is not in the SetUp menus; in that case it goes it goes back to the first item in the IQ menu All seems perfectly logical

http://fujifilm-dsc.com/en/manual/x-t3/menu_setup/button-dial_setting/index.html#edit-save_quick_menu

My X-T3 works fine with that version - your image shows X-T30

I hadn't realised it had been added with a firmware update - but I just checked and it arrived with firmware version 2.0. There is a more recent pdf version of the manual online which includes this function. It actually implies that the update allowed you to prevent shooting without a card: "Addition of "Shoot Without Card" mode With the update, you can have the “Shoot Without Card” mode turned OFF so that the camera cannot shoot when there is no SD card inserted."

It allows you to shoot without any card at all. I guess their thinking is that if you have chosen to shoot raw plus jpeg then you obviously need both cards. If you want to take a card out you could switch to sequential.

Are you saying that it works ok in FHD and the only change you make is to 4K? No other change?

Menu => Set Up => Button/Dial Setting => Edit/Save Quick Menu Press menu and find "Select Custom Setting" Press back to Save

Here is the list of compatible cameras: https://fujifilm-x.com/en-gb/support/compatibility/software/x-raw-studio/