LL boots up sluggish, becomes 'snappy' on logoff/logon

[Cedarviola]

Well, I've been trying this or that to nail it down, and the one reproducible step is that booting up from a power-off state triggers the problem. A reboot from the GUI, or log off/on it works fine.

Other things I've tried ...
Drivers -- no 3rd party drivers are installed.
Updates -- are set to manual and that was accomplished this morning picking up just a few things.
Originally it was set to auto-logon, so I edited lightdm.conf to turn it off and same problem.
Created a new user with same admin priviledges NO problem with or without auto-login.
Tried live boot from the USB and no problem.

Thinking that this is either a bug or user error, I tried sudo 'apt-get redemption', but that did not help at all
Seriously perhaps it is some UI tweak I've made or something I've installed.
Installations include Pale Moon, psensor, gqrx (rtl-sdr software) and think that's all. I could try backing those out...

Or I could try the restore point I made. Or I could re-install the whole thing. Or I could live with it 'cause when she is good she's very very good. LL has breathed new life into this old laptop.

regards
Jim