Your comments

The orientation feature is useful at comparing fields in the same orientation you have obtained in a observatory, it is then useful to identify sources, features, etc.

The same applies for the flipping: Esasky represents the sky as seen by eye, but the image taken from some telescopes/camera configurations will be reversed. As an example see an image I obtained from my observatory ;-)

If you search NGC891 in ESA sky you will see that is mirror inverted which makes the identification of sources more difficult

Pls take this as a suggestions, the tools is perfectly useful as is....

Thats nice!. I suggest to maintain the issue open util the numeric filtering is implemented.

I wonder if a SQL-like filtering capability can be implemented for sources so advanced queries can be performed.

For example to query based on magnitude:

"mag > 10 AND mag <15 ORDERED BY Name DEC"