I had a similar issue a few months back. You will have to compare the Attributes of the when it displays and when it doesn’t. There must be some custom attribute in use to determine this; look for the one that shows different when the tab is there or not… One of the ones I did used 1 and 2 for visibility, and other used a different attribute all together.
ashokkarale
MD_Farhan1
Ajay_Mishra
postwick
Dheerendra_vishwakarma
Anil_G
chandreshsinh.jadeja
Gautham_Pattabiraman
vrdabberu
aravindbalineni123