As stated on the title, if you change one item on one of your character, the visualization filter on your items (and shop's items) change accordingly. Eg: I changed the Woodman's Axe for a Bulky Club and the visualization filter change (from All Items to Weapons) Only a minor trouble: I prefer to change myself the filter if I need to.
I believe the deal is this: if you click on an item on the character sheet, the filter changes. This seems to be a "feature not a bug" intended to let you filter through all of a character's different slots without having to remember what they are called. What you described, though, might be a place for improvement. Click-dragging-and-dropping an item into a slot. I'm guessing that the code is treating this the same as a conscious "click to filter" by the player. I could see it would be easier on your inventory management if this did not invoke filtering.
See how you go with this feature over time. I find it useful but we can consider changing it if the consensus is that you'd rather have it turned off.
