Comment # 42 on bug 1084603 from Nicholas Harvey

Another observation having just inadvertently 'fixed' my issue relating to the
lack of persistence of the paragraph settings:

I just downloaded TB 60 Beta 4 from Mozilla's web site:

https://www.thunderbird.net/en-US/channel/

I unpacked it, and in the terminal CD'd to the new directory and launched TB 60
by typing "./thunderbird'.

This loaded TB 60 and imported my settings automatically. I quit, and
re-launched TB 52.8.0 and now observe that when I change the paragraph setting,
quit & relaunch TB, it now remembers the setting correctly.

So for me it seems the action of launching TB 60 has somehow solved the issue I
have on TB 52.8.0. OK, not a permanent fix, but hopefully useful information.
The plot thickens...!