Recovery Mode Disk Utility taking forever to unlock FileVault SSD

Lately I’ve noticed that when I boot into Recovery Mode and run DU from there it’s taking a long time to just get my internal SSD mounted. When I click on the SSD volume and hit the Mount button I bet I have to wait for 30-60 sec just to get the dialog to enter my File Vault key. During that wait there is zero GUI response or indication that I have to wait. If the cursor didn’t move I’d think the thing crashed.

Once it comes up, interestingly enough, the preselected entry there for user name is a bunch of hex garbage. If I enter my password with that it won’t authenticate. I have to select my name from the dropdown menu to get it to work. That again lags many seconds. If I move the cursor to hover over the menu bar I get the stupid spinning beachball.

I have no idea what caused this laggy behavior, but I don’t believe this has always been the way my FileVault internal SSD behaved on my MBP. Could this be Mojave upgrade related? I only finally crossed that bridge a few weeks back.

I have noticed the same behavior in recent Mojave updates.

I upgraded from El Capitan last year on a 2007 iMac (forced to when Apple dropped their end of Recovery mode when I lost my Time Machine disk and had 2 programs fighting for dominance of the CPU. I gave up and bought a new I7 iMac with High Sierra(?). This is the FIRST I’ve seen mentioned of a RECOVERY mode on any new machines.

Can you please point me to information about it? Thanks!

Recovery mode is not associated with your Mac model, it’s provided by your boot drive and updated by the macOS installer. Details at https://support.apple.com/HT201314