Select from the view menu, "Debug windows" > History
or ctrl-alt-H
Note, it only records if you pause/break/single-step the app. (watches will be recorded if you pause long enough.)
If the app runs un-interupted, then nothing is recorded.
If you get an exception, then place breakpoints at points that may be of interest.
In the break point properties you can set, that the breakpoint does not stop, but take a snapshot (including stack and watches), and you can inspect the data later.
Codetool can "find references" of a symbol, so you can find places that call/access something