alacritty: Incorrect cell size with FreeType fonts containing SVG glyphs

I’m running a mixed-DPI system on Wayland, and since a recent system upgrade have noticed that Alacritty’s cell size and scaling is incorrect, leading to rendering issues.

I note the cell size has a row height of 1 even after scaling calculation. I also not an erroneous scale factor of 2.0 even though the display has a custom scale of 1.6 set.

System

OS: Linux 5.18-rc5, Sway/Wayland (git head) Version: Version 0.11.0-dev (ad3ebba5)

Logs

alacritty -vv

[0.000000513s] [INFO ] [alacritty] Welcome to Alacritty
[0.000020223s] [INFO ] [alacritty] Version 0.11.0-dev (ad3ebba5)
[0.000030320s] [INFO ] [alacritty] Running on Wayland
[0.000350593s] [INFO ] [alacritty] Configuration files loaded from:
                                     "/home/ryan/.config/alacritty/alacritty.yml"
[0.000450505s] [DEBUG] [alacritty] Loading "Source Code Pro" font
[0.003180789s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Regular, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.003799465s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Bold, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.004404253s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Italic, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.005029226s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Bold Italic, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.005298649s] [DEBUG] [alacritty] Estimated scaling factor: 1
[0.005303348s] [DEBUG] [alacritty] Estimated window size: None
[0.005305826s] [DEBUG] [alacritty] Estimated cell size: 9 x 1
[0.023991131s] [INFO ] [alacritty] Running on AMD Radeon VII (vega20, LLVM 14.0.0, DRM 3.46, 5.18.0-rc5-crackotage+)
[0.024007439s] [INFO ] [alacritty] Using OpenGL 3.3 renderer
[0.026859802s] [INFO ] [alacritty] Display scale factor: 1
[0.026870120s] [DEBUG] [alacritty] Filling glyph cache with common glyphs
[0.032727780s] [INFO ] [alacritty] Cell size: 9 x 1
[0.032743722s] [INFO ] [alacritty] Padding: 0 x 0
[0.032746229s] [INFO ] [alacritty] Width: 800, Height: 600
[0.033171900s] [INFO ] [alacritty] PTY dimensions: 600 x 88
[0.037461805s] [INFO ] [alacritty] Initialisation complete
[0.045797019s] [DEBUG] [alacritty_terminal] New num_cols is 141 and num_lines is 1313
[0.049704101s] [INFO ] [alacritty] Padding: 0 x 0
[0.049720087s] [INFO ] [alacritty] Width: 1272, Height: 1313
[0.060586549s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Regular, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.061197837s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Bold, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.061779894s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Italic, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.062400138s] [DEBUG] [crossfont] Loaded Face Face { ft_face: Font Face: Bold Italic, load_flags: TARGET_LIGHT, render_mode: "Normal", lcd_filter: 1 }
[0.062679153s] [INFO ] [alacritty] Font size changed to Size(21) with scale factor of 2
[0.065081724s] [INFO ] [alacritty] Cell size: 9 x 1
[0.065093098s] [DEBUG] [alacritty_terminal] New num_cols is 282 and num_lines is 2626
[0.074493851s] [INFO ] [alacritty] Padding: 0 x 0
[0.074508658s] [INFO ] [alacritty] Width: 2544, Height: 2626

swaymsg -t get_outputs

Output DP-1 'Dell Inc. DELL P2415Q D3C8X4C50E8L'
  Current mode: 3840x2160 @ 59.997 Hz
  Position: 0,270
  Scale factor: 2.000000
  Scale filter: nearest
  Subpixel hinting: unknown
  Transform: normal
  Workspace: 1
  Max render time: 3 ms
  Adaptive sync: disabled
  Available modes:
    3840x2160 @ 59.997 Hz
    2560x1440 @ 59.951 Hz
    1920x1200 @ 59.885 Hz
    1920x1080 @ 60.000 Hz
    1920x1080 @ 60.000 Hz
    1920x1080 @ 59.940 Hz
    1920x1080 @ 50.000 Hz
    1920x1080 @ 30.000 Hz
    1920x1080 @ 29.970 Hz
    1920x1080 @ 25.000 Hz
    1920x1080 @ 24.000 Hz
    1920x1080 @ 23.976 Hz
    1600x1200 @ 60.000 Hz
    1680x1050 @ 59.997 Hz
    1600x900 @ 60.000 Hz
    1280x1024 @ 75.025 Hz
    1280x1024 @ 60.020 Hz
    1440x900 @ 59.997 Hz
    1280x800 @ 59.997 Hz
    1152x864 @ 75.000 Hz
    1280x720 @ 60.000 Hz
    1280x720 @ 59.940 Hz
    1280x720 @ 50.000 Hz
    1024x768 @ 75.029 Hz
    1024x768 @ 60.004 Hz
    800x600 @ 75.000 Hz
    800x600 @ 60.317 Hz
    720x576 @ 50.000 Hz
    720x480 @ 60.000 Hz
    720x480 @ 60.000 Hz
    720x480 @ 59.940 Hz
    720x480 @ 59.940 Hz
    640x480 @ 75.000 Hz
    640x480 @ 60.000 Hz
    640x480 @ 59.940 Hz
    640x480 @ 59.940 Hz
    720x400 @ 70.082 Hz

Output DP-2 'Eizo Nanao Corporation MX315W 0x00009D25' (focused)
  Current mode: 4096x2160 @ 59.983 Hz
  Position: 1920,0
  Scale factor: 1.600000
  Scale filter: linear
  Subpixel hinting: unknown
  Transform: normal
  Workspace: 3
  Max render time: 3 ms
  Adaptive sync: disabled
  Available modes:
    4096x2160 @ 59.983 Hz
    3840x2160 @ 59.997 Hz
    1920x1200 @ 59.983 Hz
    1920x1080 @ 59.983 Hz
    1600x1200 @ 60.000 Hz
    1680x1050 @ 59.983 Hz
    1280x1024 @ 60.020 Hz
    1440x900 @ 59.983 Hz
    1280x800 @ 59.983 Hz
    1280x720 @ 59.983 Hz
    1024x768 @ 60.004 Hz
    800x600 @ 60.317 Hz
    640x480 @ 59.940 Hz
    720x400 @ 70.082 Hz