How do you get your partners relatives to like you?

I’m meeting my girlfriend’s grandparents for the first time next week and I’m SO nervous. I don’t think they will like me, and my girlfriend keeps warning me that they will probably be rude 😅 (which is basically confirming that they won’t like me).

At least my girlfriend doesn’t really value their opinion, and it won’t matter to her at all what they think, but still, I’d like to make a good impression.

Any tips?
How do you get your partners relatives to like you?
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