dontcoz wrote: ↑Sun Nov 19, 2017 8:57 pmis it a big deal if
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as the title says
And nowhere you mentioned SEO concerns? Do you understand that links (either textual or thru pictures) to websites or pictures can leave your website scope? The resource may not even support HTTPS, so it can't be your fault to not use HTTPS in the link - likewise it may
only support HTTPS and no HTTP anymore (not even a redirect). And search engines should know/understand that better than most of the website owners.
Alternatively you can make it your philosophy to not link to resources anymore that don't support HTTPS (but I have to yet see a person being this consistent).