Config dependent behavior of Calculate Folder Sizes

I've been trying for a while to figure out why Calculate Folder Sizes produces a UAC prompt when I'm using my normal config, but not when a default config is being used.

First I discovered that the UAC prompt happened only when the operation was being done on an entire partition and then because my config does not have Hide protected operating system files checked whereas a default config does and $RECYCLE.BIN and/or System Volume Information cause the UAC prompt.

One oddity remains. After using Edit -> Calculate Folder Sizes and clicking Yes on the UAC prompt, the calculation immediately happens.

After pressing Ctrl+L and clicking Yes on the UAC prompt, nothing happens most of the time though after doing it repeatedly for a seemingly inconsistent number of times, the calculation seems to happen.

I'd be surprised if using the hotkey vs menu would make a difference, since they should run the same command ultimately.

Are you sure it isn't waiting for a previous calculation to finish? Calculating the size of a whole drive can take a while.

That's what I thought.

But again, neither method should take longer than the other, right?

Later:

I'm still not completely sure what Ctrl+L is doing, but I now know why it sometimes behaves differently than the menu.

The first file is $RECYCLE.BIN which currently has a size of 1,276. This is consistently shown using the menu.

It's also consistently shown (after the UAC prompt) if I press Ctrl and L in rapid succession.

However, if I'm slow getting to L after Ctrl a "size" of ~1,147(?) appears while Ctrl is pressed. If I then press L (with Ctrl still down), the UAC prompt appears. When Yes is clicked, the ~1,147is immediately cleared and nothing else is calculated.

Maybe the real question here is why does pressing Ctrl by itself cause the size of the first folder to be calculated.

Before pressing Ctrl:

After pressing and holding Ctrl:

Holding the control key down triggers the infotip for the item with focus, and the default infotip for folders includes the folder size.

I didn't know that. I see it does do that, but also puts the size in the size column apparently.

Maybe we're getting into a semantics issue now. I see that holding the control key down does indeed do the same as hovering on the item which is display the info tip and put the size in the size column, but that seems independent of the info tip. I removed size from the info tip and still get both the info tip (without size) and the size in the size column.

At this point, I accept that whatever is happening is probably by design.

There is still an oddity in that hovering on (or Ctrl) a protected system file ($RECYCLE.BIN) doesn't give the same size as Calculate Folder Sizes and also doesn't produce a UAC prompt which are probably related.

Curious, but probably not worth more time.

It puts the size in the size column because it might as well, if it's calculating it anyway.

UAC prompts are blocked when the calculation comes from the info tip since having to OK a UAC prompt just to show a tooltip would be rather weird/unexpected.