Hello! 
I just tried TeamViewer on the Raspberry Pi 3 and it gobbles up a lot of RAM. This didn't happen about 6 months ago, so I hope it will be fixed rather soon.
Technical info:
- Raspberry Pi 3 model B, resolution 1920x1080, 76MB GPU memory
- fresh image of Raspbian (2019-09-26-raspbian-buster.zip), fully updated
- TeamViewer 14.6.2452 H
- no other software started manually or automatically during the test
Here are the steps I made and how the RAM usage looked like. By RAM usage I mean the total amount (all processes) reported by the LXDE Task Manager. Also please note that after each step I waited for at least 15-20 seconds for the RAM usage to settle:
1. [138MB] Fresh boot with the TeamViewer service started (icon in the systray)
2. [533MB] Remote connection established
3. [542MB] TeamViewer Host window unminimized
4. [677MB] Clicked the feedback/about dropdown menu in the TeamViewer Host window
5. [801MB] Clicked About and the About window is displayed
6. [798MB] Closed the About window
7. [796MB] Closed the TeamViewer Host window (systray icon still active)
8. [803MB] Clicked systray icon and opened the TeamViewer Host window again
9. [804MB] Clicked the feedback/about dropdown menu in the TeamViewer Host window
10. [824MB] Clicked About and the About window is displayed
11. [824MB] Closed the About window
12. [822MB] Closed the TeamViewer Host window (systray icon still active)
13. [747MB] Closed the TeamViewer session (systray icon still active)
As you can see, there's some, but not much of an effect by repeating steps #4-7, and subsequent repeats won't generate any significant fluctuations in RAM usage. I didn't check the swap usage because I didn't want to start more processes and "pollute" this test. Then I started a new session:
1. [850MB] Started a new TeamViewer session after I closed the previous one
2. [836MB] TeamViewer Host window unminimized
3. [837MB] Clicked the feedback/about dropdown menu in the TeamViewer Host window
4. [848MB] Clicked About and the About window is displayed
5. [844MB] Closed both the About and Host windows
6. [749MB] Closed the TeamViewer session (systray icon still active)
The good thing is this time the Pi's OS didn't freeze in this last test, like it did 2 times before, but obviously TeamViewer should (1) free the RAM that it no longer needs and (2) try to use less RAM, because there's not much else you can do if your RAM usage is at 850/926MB.
Oh, wait... I thought I might as well try another session and the OS froze again.
