Why has my LibreOffice help screen suddenly got very very small writing and how can I enlarge it?

I use the help function quite frequently and to date it has worked well. Yesterday however when I pressed F1 and the help screen appear the left hand part of the screen is fine but the main part on the right the writing has become too small to read and I cannot see any way of enlarging it (CTRL and + doesn’t work). I am now seeking help by other means.

I can now answer my own question. I was having adifferent problem in LibreOffice and to see if it helped I opened it in SAFE mode. Doing this not only resolved my other problem (well, partially) it also returned my help file writing to the correct size.