This is relevant if the implementation of a tracking pixel changes the looks of your site - this is typically where a white box or line is added unintentionally.
This is probably because an extra paragraph is added to your coding. By adding the following to your tracking pixel, the white space will be moved out of sight:
The tracking pixel should then look similar to this:
After this change, make sure to keep an eye on your campaign in AudienceReport to secure that the pixel is collecting data as it should.