[Bug]: Game switches to fallback font when refreshing

Version of OpenTTD

20240511-master-g721cd2b8ad, Windows 11 Home (Simplified Chinese)

Expected result

When changing the font via the font command, the game will automatically use the requested font and will not change it after refreshing the game, restarting, or abandoning a game.

Actual result

After changing the font via the font command, the text does use the glyphs in the requested font; however after restarting or abandoning a game an error message saying "switch to fallback font" appears and the text starts to use the fallback, which, on my system is 微软雅黑(YaHei).

Tested with Unifont, Unifont-JP and 寒蝉全圆体 (ChillRound)
fonts.zip

Steps to reproduce

1. (May be unnecessary) switch system language to Simplified Chinese;
2. Change game language to Simplified Chinese
3. start the console and type the following commands:

font medium "" 0 aa
font medium (font) 0 aa // font == Unifont-JP, Unifont or "寒蝉全圆体"

4. Start a new game, or open the game options menu
5. close the game options menu, or abandon the game
6. notice that the font changes

Start with the console font command and reproduce the fallback after opening and closing the game options or abandoning a game; then trace how the selected font is retained across those lifecycle transitions. Done means the requested font remains active after refresh, restart, and abandoning a game, with no fallback-font error.