Space between message groups is shared between comfy and dense modes except at default values

Observed behaviour

The setting is shared when "custom" but setting it to the current mode's default value resets both to their respective default values (making them effectively separate)

Reproduction steps

Go to settings → look and feel → messages
We're looking at the relation between either of the two modes (comfy/dense) and the "Space between message groups" slider. We can observe two different behaviours:
If we set either of the modes to any of the non-default space values, that value is conserved between modes.
If one of the mode's space value is on its default value (comfy: 16px, dense: 0px), switching to the other one will jump the slider to its respective default value.

Build information

canary build 731 (1c756a2), Electron 41.2.2, Linux 7.0.5-2-cachyos (x64), desktop canary 0.0.208, Electron 41.2.2, Chrome 146.0.7680.188, Node 24.14.1, locale en-GB

Platform

Linux

Details

Expected behaviour Either the setting is shared between modes, or each mode has its own separate value.