Star Trek: The Next Generation - Someone Still in Another Time
At the very end when Guinan asks La Forge to tell her about Tasha Yar, La Forge has on the uniform from the other timeline. You can tell because the end of the sleeves are black.
Its realy noticable. I'm surprised they did catch it when they were editing the film. The uniform he wears in the currect time line has a plain yellow sleve. The one he wore in the alternate timeline had a black cuff on it. That black cuff can be clearly seen at the end of the episode after history had been restored.