Usually, when specifying text objects which are invalid, the missing glyph (hollow rectangle) is displayed, as is often seen with currently unsupported characters. However, in the specific case where the atlas specified is valid, but the specific sprite is not, the missing texture will be displayed.
Since the missing texture is only meant to be visible when resource packs or data packs are broken, having it show up when no resource packs or data packs are applied besides the default indicates that there is an issue.
To reproduce:
/tellraw @s {atlas:"bugs",sprite:""}
/tellraw @s {atlas:"blocks",sprite:""}
Expected: both of these would display the rectangular tofu glyph for an unsupported character.
Actual: the first correctly does this, but the second shows the missing texture.
How to fix: invalid sprites on valid atlases as text objects should be made to use the missing glyph as a fallback.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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