I like the fact that you've used video game style colour coding for items of different rarity. It acts as a nice visual shorthand. Of course, you have to learn that visual shorthand first before it is useful. This would be easier if everything about the system reinforces it. Hence, I suggest that the rarities in the drop down filter are similarly colour coded (or if this comes up against technical limitations, the appropriate colour is listed in brackets or something).
Additionally, I don't know whether this is already planned, but any time a magic item is mentioned across D&D beyond it should be similarly colour coded (and hyperlinked, as people have already suggested for spells).
I like the fact that you've used video game style colour coding for items of different rarity. It acts as a nice visual shorthand. Of course, you have to learn that visual shorthand first before it is useful. This would be easier if everything about the system reinforces it. Hence, I suggest that the rarities in the drop down filter are similarly colour coded (or if this comes up against technical limitations, the appropriate colour is listed in brackets or something).
Additionally, I don't know whether this is already planned, but any time a magic item is mentioned across D&D beyond it should be similarly colour coded (and hyperlinked, as people have already suggested for spells).