Filtered Lookup OK Button disabled.

I was, facing a weird issue in the filtered lookup configured through the JavaScript.

This is what the issue was: I was, able to see the filter happening, But, when I open a look up, the OK button to select one, was disabled.

Solution: In the Layout Xml, I had a different Id field of another entity (Please, fallow the below line of code to find an ID). Also, if you make any typo while defining an Id field, you will face this issue (OK button disabled).

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Hope, this helps.