Thanks to everyone who has taken the time to reply.
I'm not a security expert ... not by a long chalk.
However, I have been forced to acquire some knowledge.
Here is a guide to Lets Encrypt -
https installed for free (in 15 minutes) using cPanelIt also outlines the critical https redirect code (which is a life saver)
Strangely enough, if you search for 'https installed for free' in DuckDuckGo - it is literally nowhere in the results, with all sorts of 'install stuff' appearing high up.
But still ... 2.5k views
Let's encrypt then sends out an email to remind you that the script is about to expire.
Once you are organised, with saved tabs, the whole process can be completed in around 6 minutes, with zero stress.
Of course, all security is severely limited.
I work on the assumption that everything that I do is open to scrutiny.
However, the https does avoid the Firefox security warnings to users - which I believe is an important factor.
I presume that, for a forum, the difficulty would be in arranging the certificate upload and replacement, without a CPanel site controller.
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Re the forum ... I'm uncertain.
Everything yesterday was a blur ... attempting to quickly get on top of 'a subject home', due to time being short.
Never a good idea.
I had 3 options - yourselves and proboards and createaforum.
I set up the forum, with you first, but there were these issues as discussed.
There was no clear information indicating payment options ... I found it only after you chaps pointed it out to me.
Even then, it was a struggle to find out what the points were costing.
As it happens, your costing is competitive.
However, by this time, I had checked out proboards, and paid $4.80 for the privilege.
Then I discovered that Firefox was showing a security warning, with their login redirect page.
Late at night, hot, sweaty, and being bitten by mosquitos ... it was 'head in hands' scenario.
Anyway...
Both you and proboards provided support.
Proboards stated that Firefox was in error.
Chrome doesn't provide any redirect page warning, but in my experience Firefox is more accurate with its security warnings.
(Chrome seems to block any site with interesting info, that loads perfectly in Firefox).
So what to do?
I now have two forums with the same name.
What are pros and cons?