A bug with using Cinnamon and Coverflow (3D) OR Timeline (3D) on multiple screens

• Cinnamon version (cinnamon --version): 4.8.6
• Distribution - (Mint 17.2, Arch, Fedora 25, etc...): Mint 20.1
• Graphics hardware and driver used: AMD Radeon 5500
• 32 or 64 bit: 64b
• Extra: A selection of inxi -Fxxxrz run in terminal:
  System:
  Kernel: 5.4.0-67-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: Cinnamon 4.8.6 wm: muffin 4.8.1 dm: LightDM 1.30.0 Distro: Linux Mint 20.1 Ulyssa base: Ubuntu 20.04 focal
  Machine:
  Type: Desktop System: Gigabyte product: X570 AORUS PRO v: -CF serial: Mobo: Gigabyte model: X570 AORUS PRO v: x.x serial: UEFI: American Megatrends v: F32 date: 01/18/2021
  CPU:
  Topology: 8-Core model: AMD Ryzen 7 3700X bits: 64 type: MT MCP arch: Zen L2 cache: 4096 KiB flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm bogomips: 114985 Speed: 2158 MHz min/max: 2200/3600 MHz boost: enabled Core speeds (MHz): 1: 2158 2: 2158 3: 4314 4: 2158 5: 2195 6: 2195 7: 2196 8: 2196 9: 4316 10: 2158 11: 2196 12: 2196 13: 2196 14: 2196 15: 2158 16: 2158
  Graphics:
  Device-1: AMD Navi 14 [Radeon RX 5500/5500M / Pro 5500M] vendor: Gigabyte driver: amdgpu v: kernel bus ID: 0a:00.0 chip ID: 1002:7340 Display: x11 server: X.Org 1.20.9 driver: amdgpu,ati unloaded: fbdev,modesetting,radeon,vesa resolution: 3440x1440 75Hz, 3440x1440 75Hz, 1920x1080 60Hz OpenGL: renderer: Radeon RX 5500 XT (NAVI14 DRM 3.35.0 5.4.0-67-generic LLVM 11.0.0) v: 4.6 Mesa 20.2.6 direct render: Yes

Issue
Since a few months I have three screens, a '24 HD on the left, and 2x 32' WQHD in the middle and right. Whereas my '24 in lower than my other two '34 screens. When using Coverflow (3D) OR Timeline (3D)* to switch between the apps that are open, I see the wallpaper from my middle screen stretch across the two other screens, with space left on my left screen (the lower part, because I have set this '24 lower than the other two '34) and space left on my right screen. Thus by using Coverflow/Timeline, it use my wallpaper of my screen in middle and stretch it out over all three screens.
I have it enabled by doing the following: Start menu > Windows > Alt-Tab > Coverflow (3D) OR Timeline (3D)

Steps to reproduce
Using Coverflow (3D) OR Timeline (3D) and start switching between the open apps.

Expected behaviour
That Coverflow/Timeline do not stretch my wallpapers, but is just hovering over it, when using it.

Start at Start menu > Windows > Alt-Tab and reproduce the issue with Coverflow (3D) or Timeline (3D) across the three differently positioned screens. Trace the Cinnamon/Muffin implementation for these switchers; done means the middle screen's wallpaper is not stretched across the other displays while switching applications.