Comment 10 for bug 1880405

Similar ERROR in /var/log/syslog for me on Ubuntu 20.10 with gnome-shell 3.38.1-1ubuntu1.1. Similar to comment #9 I have firefox with many tabs and dissenter (brave fork) with many tabs open.

Jan 4 06:43:29 desktop01 gnome-shell[2096000]: JS ERROR: TypeError: null has no properties#012_onFocusChanged@resource:///org/gnome/shell/ui/closeDialog.js:135:9

Jan 4 06:43:30 desktop01 gnome-shell[2096000]: message repeated 35862 times: [ JS ERROR: TypeError: null has no properties#012_onFocusChanged@resource:///org/gnome/shell/ui/closeDialog.js:135:9]

Jan 4 06:43:30 desktop01 gnome-shell[2096000]: JS ERROR: TypeError: windowActor is null#012_addWindowEffect@resource:///org/gnome/shell/ui/closeDialog.js:90:28#012vfunc_show@resource:///org/gnome/shell/ui/closeDialog.js:162:14

➜ ~ inxi -SMCG
System: Host: desktop01 Kernel: 5.8.0-33-generic x86_64 bits: 64 Desktop: N/A Distro: Ubuntu 20.10 (Groovy Gorilla)
Machine: Type: Desktop System: ASUS product: All Series v: N/A serial: <superuser/root required>
           Mobo: ASUSTeK model: X99-A v: Rev 1.xx serial: <superuser/root required> UEFI: American Megatrends v: 4101
           date: 07/10/2019
CPU: Info: 6-Core model: Intel Core i7-5820K bits: 64 type: MT MCP L2 cache: 15.0 MiB
           Speed: 1765 MHz min/max: 1200/3600 MHz Core speeds (MHz): 1: 1626 2: 1243 3: 1387 4: 1291 5: 1379 6: 1316 7: 1329
           8: 1300 9: 1288 10: 1247 11: 1356 12: 1282
Graphics: Device-1: NVIDIA GK208B [GeForce GT 710] driver: nvidia v: 455.38
           Display: x11 server: X.Org 1.20.9 driver: nvidia unloaded: fbdev,modesetting,nouveau,vesa resolution:
           1: 2560x1080~60Hz 2: 1680x1050~60Hz
           OpenGL: renderer: GeForce GT 710/PCIe/SSE2 v: 4.6.0 NVIDIA 455.38