Metatags are always seen as changed.

Hello,

Thank you for this nice module.
I have seen that metatags were always seens as "changed fields", even if the values themselves were not changed at all.

I do not know if it is an issue in the metatag module or in this one but I am still reporting it just in case.

For information, I have those metatags modules installed:
metatag
metatag_open_graph
metatag_twitter_cards

Cheers!