@jlfranklin mentioned Database SSL Check in https://github.com/backdrop/backdrop-issues/issues/4772#issuecomment-778.... That is a D7/D8 module, and it could of course be ported to Backdrop contrib, but it's only a ~40-line implementation of hook_requirements(): https://git.drupalcode.org/project/database_ssl_check/-/blob/7.x-1.x/dat... ...so I believe that it could be a nice addition to core, as part of #3624.
I've installed the module in Backdrop (simply modifying it's .info file), and this is what it adds:

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Worth mentioning as it was in zulip chat by @yorkshirepudding I just tested and the two work together without issue as long as you don't use the "Exclude comments from Content...
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There is also Node Comments Search - this searches the node and all comments (default search is node and first page of comments) as part of the content search. Izzy's module above is a separate...
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I have created a new module comment_search
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