don't use copper grease, wd40, oils or any petroleum based lube on rubber seals cos it gets absorbed into the petroleum based rubber making it slowly swell up permenantly over time till it binds & dries up (uneven wear from binding guide pins), which then makes removal & reassembly slightly more difficult next time.
suggest using non petroleum grease like silicone paste or red rubber grease or stuff labelled for rubber
I've been using waterproof grease for mountain bike hubs for ages... Cheap and never given me grief