Problem trying to setup JRE on LibreOffice 6.3.1.2 Ubuntu 18.04

Hi I’ve been trying to setup JRE on LibreOffice 6.3.2 running on Ubuntu 18.04 to get the Zotero extension to work.
When I go to Tools → Options → Advanced I always find the “Use a Java runtime environment” box unchecked, and the box underneath empty, though I know JRE is installed and indeed when I add one manually it does appear in the box with the little dot checked.
So, once this is done I click Apply and OK but when I open the Tools → Options → Advanced dialog again, it shows the “Use a Java runtime environment” box unchecked again, and the box underneath empty.

How do I get LibreOffice to save my preferences?
(I have JRE 1.8.0_181 installed).

it does appear in the box with the little dot checked.

Just to be sure: Your really clicked the radio button once. It is not checked automatically, even if there is only a single JRE installed?

It was checked when I added it manually, but I unchecked it and checked it again to no avail. Once I close and reopen the Options dialog everything has disappeared.

Did you already try to reset your user profile? (Just made a test in my ubuntu test system and a did not see any problem - though my ubuntu comes with OpenJDK 11.0.4). Where did you get JRE 1.8.0_181 from (and you assured correct bitness - 32-bit vs. 64-bit)?

I just reset the user profile and it worked thanks!

For the record (according to last comment of @Mazel Dogg)

Reset your user profile following instructions at https://wiki.documentfoundation.org/UserProfile.