i've recently read on github that someone ask if is possible to add mutltiple rss feed url supports.
justoverclockl/flarum-ext-newsfeed1
forgot to mention that this extension actually SUPPORTS multiple feed url, simply u need to insert multiple urls separated by comma, but remember that actual settings fetch 5 element from EACH url...
so if u add 2 url, results is that u have 10 elements displayed, that need a css customization, or it will look like this example (here u can see 2 rss url togheter):
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this post is just to clarify that this extension actually support mutiple rss url