I have placed my post in this discussion area; it appears that no one has an answer or idea to this problem, even though quite a few people have read this post since the middle of August. I hope this area will produce a better response:
I would like to offer a suggestion to all of the developers working on all releases of Ubuntu: Please incorporate a native font manager into the OS; this would simplify the steps needed to add, remove, and locate font files, and allow non-technical users (including me) the pain of dealing with system issues that may arise from compromised or improper software to manage font libraries. I ask that you consider this in upcoming releases of Ubuntu.
The reason why I am asking is: 1. The font managers available on Synaptic have not worked well on my machine, which is 32-bit. I have used Caja to remove a few "unnecessary" files, such as the majority of fonts in the Noto family. I would like to see LibreOffice offer a built-in font manager, if the developers decide against including a native manager with the OS. I have also run into compatibility issues: maybe the font managers are not compatible with 32-bit processors. 2. Where do I find the folders containing fonts that I have installed in my system? I have tried "/usr/local/share/fonts," but the files are not listed there. In 2007, I could easily find my installed fonts, but it's not as easy in 2018. Please help me understand more. Thank you.