Zooming shortcuts do not work under Wayland if font size is not an integer

[theCapypara]

Describe the bug
This issue took me ages to figure out:

If using Wayland and the font size is currently not set to an integer (eg. 20,2), then zooming via the zoom in/zoom out shortcuts does not work. It works under X11.

Expected behavior

The font size should increase / decrease.

Actual behavior

Nothing happens.

To Reproduce

1. Run Wayland (I used GNOME 45)
2. Configure the zoom shortcuts
3. Set the font size to an non-integer value
4. Try to zoom in/out using the configured command.

---

$ guake --support

Guake Version: 3.11.dev0

Vte Version: 0.74.1

Vte Runtime Version: 0.74.1

---

GTK+ Version: 3.24.38

GDK Backend: <GdkX11.X11Display

---

Desktop Session: gnome

---

Display: :0

RGBA visual: True

Composited: True

• Monitor: 0 - DP-7
  • Geometry: 2560 x 1440 at 1920, 0
  • Size: 600 x 340 mm²
  • Primary: True
  • Refresh rate: 59.912 Hz
  • Subpixel layout: unknown
• Monitor: 1 - eDP-1
  • Geometry: 1920 x 1200 at 0, 240
  • Size: 300 x 190 mm²
  • Primary: False
  • Refresh rate: 59.884 Hz
  • Subpixel layout: unknown
• Monitor: 2 - DP-6
  • Geometry: 2560 x 1440 at 4480, 120
  • Size: 600 x 340 mm²
  • Primary: False
  • Refresh rate: 59.912 Hz
  • Subpixel layout: unknown

[theCapypara]

This is probably too niche of an issue to actually bother prioritising but I hope someone with the same issue stumbles upon this 😅
I was going crazy trying to figure out why zooming didn't work for over a year now. It worked perfectly fine under Wayland on another machine of mine, I thought some other app was interfering with shortcuts somehow....

[JoshuaS3]

Unchecking this box in preferences, manually selecting the font family and size fixed it for me:

Guessing there's some bad floating point type casting stuff happening here? The "actual behavior" for me was basically setting to random/unpredictable zoom levels, erratic. Not sure. I initially installed/ran/configured Guake running under Wayland and switched back to X11 at some point.