Running a process with DevTools debugger attached leaks memory

- Version: 14.0+ (reproduced on `v14.0.0`, `v14.17.0` and `v16.1.0`) - Platform: Linux - Tested process: https://github.com/Supinic/supibot - Valgrind tests by: https://github.com/Leppunen While the Chromium DevTools debugger is attached, RSS memory usage of a Node process keeps increasing without being collected. Once the debugger is detached, the memory usage flattens, however the memory is never released. When the debugger is not attached to the process in its runtime, memory allocation occurs as expected. It is entirely possible that this might not be related to Node (v8, perhaps) - however, this issue might be a good place to start a discussion. Inspecting `htop` on a Raspberry Pi 3B machine: - Process after running for ~24 hours without a debugger attached: stable at around ~180MB RSS:  - The same process, after attaching the debugger for ~15 minutes (with no actual user debugging active nor any logs being displayed): RSS at around ~245MB and rising:  - After disconnecting the debugger (removing the connection, closing and re-opening the debugger window), RSS stabilizes at around ~260MB. After ~30 minutes of further activity, the RSS usage seems stable; however, the memory is not freed:  After running valgrind for various amounts of time on a different Linux machine, there seems to be an excessive amount of `v8_inspector::AsyncStackTrace::capture` calls. Using the `Disable async stack traces` option in `DevTools > Settings > Debugger` seems to reduce the leak somewhat, however, this wasn't reproducible across machines. Furthermore, testing the same process on Windows 10 in the same environment leads to no memory leaks. Attached…