I've been used a number of email plugins in the past (360Works, CNS, Dacons, etc.) and all work well. But noticed that the free and popular Base Elements plugin also supports SMTP emails including HTML. Sounds really good, so I thought I would try it out. Documentation on these is at BaseElements Plugin Help Centre
So I thought I would try this out. Basically it looks easy to use if you just use port 25 and no SSL/TLS, which my mail servers require. Fortunately, Base Elements supports setting CURL options for the SSL/TLS with the BE_Curl_Set_Option function. Except, I can find an example that sets the appropriate CURL options to make a standard HTML email with SSL (TSL 1.2) on port 587.
If someone else has an example script like this that works, that would be helpful. Maybe if we get an example we could get Goya to post it on their documentation web site too.
By the way, thank you Goya for your plugin that you provide for free to the FileMaker community. I see there is a way to help provide support for the plugin too which I think I'll do just to help out with future development!