Some of the filters that I create for work can get pretty lengthy.

It would be super useful to have color-coding to help keep track of where each query starts and ends, similar to writing formulas in Excel.

Excel example:

 

An example query I've used for work:

issueFunction in portfolioChildrenOf("Team = 90") AND ((issueFunction in portfolioChildrenOf("Key in (DAF-1348, DAF-2685, DAF-19951, DAF-4807, DAF-8063, DAF-11468, DAF-1959)") OR Key in (DAF-2891)) AND type in (Task, "Master Task") OR labels = Daf_test) AND resolution is EMPTY AND NOT (issueFunction in portfolioChildrenOf("Key in (DAF-12540, DAF-23431)") OR key in (DAF-11475, DAF-11476)) AND summary !~ "16-Design"

It'd be easier to read and troubleshoot if color-coded:

issueFunction in portfolioChildrenOf*("Team = 90")* AND ((*issueFunction in portfolioChildrenOf("Key in *(*DAF-1348, DAF-2685, DAF-19951, DAF-4807, DAF-8063, DAF-11468, DAF-1959)")* OR Key in (*DAF-2891)) AND type in (Task, "Master Task") OR labels = Daf_test)* AND resolution is EMPTY AND NOT (*issueFunction in portfolioChildrenOf("Key in *(*DAF-12540, DAF-23431)")* OR key in (*DAF-11475, DAF-11476))* AND summary !~ "16-Design"