I have already suggested this by email, but I just want to make this request "official"... and see if I'm the only one who would like it (I searched the forum and could not see anything like this).
When you load a PHP document and you look at the Code Explorer tab (in the PHP view), you can expand the "Variables" tree.
If you have $var five times in your document, it will appear five times in the variables tree (one entry for each line in appears in the code). I personally don't have any use for it in its current form. What would be extremely useful to me would be to have the list grouped by variable. Each variable would appear once in the tree and you would click to expand to see the different lines that the variable appears in the code.
This way, you would have a quick way to see all the lines where $var is used. When you have 30+ different variables, it's currently really hard to visually search the tree to find all occurences of a variable.
Instead of:
> Variables
--> $var (line 2)
--> $var (line 5)
--> $var (line 14)
--> $var (line 33)
--> $var (line 42)
The tree would look like:
> Variables
--> $var
----> Line 2
----> Line 5
----> Line 14
----> Line 33
----> Line 42