If your TT-RSS installation is running over SSL/TLS and you load content from feeds that are served from a different site that is not secure then, yes, you will get mixed content warnings.
The solution is:
- Cache media; or,
- Enable the af_zz_imgproxy plugin.
The first will attempt to download and store the media on your server (which could noticeably increase the amount of storage you need since it caches images, audio and video). When enabled it caches everything at the same time it’s updating the feed, so your server has the media whether you read those articles or not.
The af_zz_imgproxy plugin by default proxies requests through your server so you don’t get mixed content warnings. It only affects articles that you actually read and it does cache the results so subsequent requests will be delivered right from your server instead of having your server fetch it on the Internet again. As the content is not immediately available on your server load times are increased because you have to request the image from your server, which then requests it from the originating server before delivering it to you.
There are pros and cons to both. I cache media for sites where I basically read every article and know I want the media (comic strips are a great example of this). I want the images to load fast, be available regardless of whether the originating site pulls the content, and I know I’m going to read the article so I want to have these images available.
For everything else I use proxy. Because I want a secure connection but don’t need to waste time and resources (both the originating server and mine) downloading everything.
e: Also make sure in
config.php that the correct
SELF_URL_PATH is defined with
https:// at the beginning.