In the "chars" list of any "bitmap" type provider, the space is no longer recognized as a padding character.

Prior to 1.19, either a U+0020 SPACE or the unicode escape \u0000 was allowed as a "blank" character in the string elements of the "chars" array. These padding characters would be skipped over; ignored.
Now, the space is instead interpreted as a real bitmap character, and will generate a flood of warnings for every space padding character when loading a font.

This is likely not intentional because when the "chars" list is uneven, the current messages say specifically to use space or \u0000, not just \u0000:

[Worker-Main-12/WARN]: Unable to load font 'minecraft:default' in fonts.json in resourcepack: 'file/Space padding font'
com.google.gson.JsonParseException: Elements of chars have to be the same length (found: 46, expected: 2), pad with space or \u0000

Now, in 1.19+, when loading a font that uses spaces as padding, thousands of

[Worker-Main-15/WARN]: Codepoint '20' declared multiple times in minecraft:textures/font/ascii.png

are generated in the latest.log.

This is likely a problem left over from the implementation of the "space" provider in 1.19.

This problem does not occur in 1.18.3 or lower.