Q: Why won't some of my feed items work with the lightbox link behaviour?
Some websites do not allow their site to be shown in windows where the domain is not their own, such as in a lightbox.
Browsers respect this choice, and this is when items imported by WP RSS Aggregator may not display correctly when the link behaviour is set to open in a lightbox.
This is a security feature implement by some websites. The intentions vary, for example, a payment gateway website may do this in order not to allow scam websites to embed PayPal on their sites in any way.
This is a limitation put upon our plugin by the source sites, and as such, there is no way around it. The wishes of the source sites are to be respected accordingly.