Request i-140 copy with FOIA while being employed with same employer?

Can I request i-140 copy while being employed with the same employer, before changing jobs?

And will my employer come to know if I request it?

Yes, you can request it anytime even when working with same employer.

Your employer will not know. USCIS does not send any information to your employer.

Step by step process to request I-140 using FOIA: