Steps to reproduce:
1. Open new project
2. In Profiler window click "Profile Editor"
3. Let it run and while looking at the Task Manager and Unity's Memory usage
4. Memory usage keeps increasing.
5. Click on the timeline to show how many frames are existing in total
6. Profiler shows all of the frames being saved even though you can't even look up their information, because profiler only shows the last x amount of frames.

Expected: Either clear the unusable frames or allow to view them
Actual: Lots of frames are still being saved even though you can't observe their information

Reproduced on:
2018.3.0b4 , 2018.3.0b1

Version 2019.1.0a3 (0e3c7820a690)
Sun, 30 Sep 2018 14:48:41 GMT
Branch: trunk

Not reproduced on: (Memory doesn't pile up while profiling editor or only a little bit)
2017.4.12f1, 2018.1.0f1, 2018.1.9f2, 2018.2.11f1, 2018.3.0a5, 2018.3.0a7, 2018.3.0a11,