I hope someone can help me out because I've been pulling my hair out over this issue LOL. I've posted this question to a couple of Olympus forums so far no responses. My hopes here are kinda slim also but decided I'd try. Not that hoggers aren't knowledgable or helpful but I suspect the number of Olympus users here is quite small and the ones that use BBF would be even smaller.
I've been trying to set up BBF on my EM5 MK2, but with no success. I've watched every Youtube video on the subject and followed their directions.
Menu> Custom Menu> AEL/AFL> S-AF> Mode 3. I then set the FN1 button to be the BBF button.
I then check the shutter button by pressing halfway and it doesn't focus. So far so good. I press the FN1 button and it focuses. So far so good. I then press the shutter button to take the picture and if I've recomposed it tries to refocus. Not good. I've ended up with numerous blurry photos I've had to delete.
Does anyone know what I'm doing wrong? Probably something obvious. Thanks for any help.

As you found in your initial research, it is related to screen resolution. Your screen has a fixed pixel resolution. When the pixels in the image are 1 to 1 to the screen, you are looking at a 100% crop. Note how the image gets 'fuzzy' when you go beyond 100% in your digital editor.

Say your high-def screen is sized 1920x1080 pixels for a 16x9 aspect ratio. When you look at an image at or larger than 1920x1080px and you 'zoom' to 100%, you are seeing just a 100% crop of the larger image for exactly a section measured 1920 pixels x 1080 pixels.

Consider your image measuring 8290 x 4560. Using my example monitor at 1920x1080 that measures 21-inches across. You'd need a monitor wider than 80-inches (4x) to see the entire image at the original 38MP resolution at 1:1 pixels to screen.

See examples and somewhat related discussion: Recommended resizing parameters for digital images

What is BIF? I just returned to Olympus OM-D EM5 MARK II after a brief "encounter" with both the Olympus first, then a Sony a7II, then FINALLY deciding on the Olympus OM-D EM5 MARK II. What or where is the best and most simple place, or source, to learn about the Olympus? Am I starting a new topic? I don't know but the Olympus menu system was the main reason I returned to the Sony after years of working with them, but I decided I want the Olympus for both the size, quality and choices of lenses. I must learn how to navigate the Olympus system. Maybe this will help this topic for both of us?