Random Items Tagged as Quest Items

[Kinomora]

I have quest cape and no active diary task to complete, yet when I have quest helper enabled random items are marked as "Quest Items" on the ground such as Law Runes in this example, but for other items too including Waterskins (4).

What is the cause of this?

[gwen-lily]

I have similar behavior, most recently this saw.

[Zoinkwiz]

Were there any remaining achievement diaries which you did not have the requirements for?

[gwen-lily]

Absolutely, this account (to this day) does not possess all the requirements for a few elite diaries, including Ardougne (where the behavior occurred)

[pajlada]

Do you have the "Always highlight needed items" setting enabled?