To "a", Well, for myself, I refrained from addressing your question earlier in the month because I am not a professional. But I am a member of a club which is not simply a free tech support hotline. We meet and discuss projects and problems of our own and trends and ideas from the various free software news fronts.
Are you aware that Adobe Flash is being retired (deprecated)? Have you been watching for changes on the internet? I do use an Ubuntu flavor, but read other distro news as well. I often start solving a problem with a search for "Ubuntu + my issue" to see what others think. Also in the trends today is the shift to 64-bit hardware and software. If you can get new hardware by whatever means, that will help. If you want to keep up a hobby machine on older architecture you will need to work harder. It's like keeping that beautiful 1950's low rider in shape - you cannot just ask for parts and solutions anywhere. It gets tricky and there are trade-offs, or losses you have to accept in an older unit.
By the way, if I am having 4 or 5 issues with an installation and fixes seem to break the system, I think to myself, "It's time to do a back-up of my files and start with a new, clean install." Have you considered that route? I strongly suggest running a supported version of Ununtu, Debian or similar operating system. Ubuntu 14.04 is still supported, but not for long, Ubuntu 16.04 is in good support. If yours is older, I would strongly recommend a review of hardware and software, plus an immediate attention to external back up.
While I know this does not answer the specifics, I wanted to reply to let you know I have read your post.
Thank you, Ted P.