When joining a world hosted on windows 10 that has required resource packs, if the crosshair is anything other than default, it will have a black box around the texture. The exact same texture on windows 10 does not have the black box. The issue was tested with multiple different resource packs.

For reference this is the resource pack being used: https://www.planetminecraft.com/texture-pack/paper-cut-out-bedrock/