Entities assigned to a team with a valid team color set do not render their glowing affect the color of the team while invisible. However, the glowing effect does represent the team color when the entity is not set to invisible.

Steps to reproduce:

Setup team

/team add GOLD
/team modify GOLD color gold

Spawn entity

/summon minecraft:magma_cube

Join entity to team

/team join GOLD @e

Add effects and observe bug

/effect give @e minecraft:glowing 100
/effect give @e minecraft:invisibility 10

Entity outline is gold before adding invisibility

Observe color as white after invisibility, the team didn't change so the color should stay the same. Bug

After 10 seconds the invisibility will wear off confirming the client didn't lose the team data for the entity.

Additional info

Attached below are images of what the visual looks like. Too further narrow down the affected code there is also an example of where the skeleton is holding an item that is correctly colored, yet the body of the skeleton is not.