The bug #0021723 is still happening even after the related issue(#23251) appears to be patched.
To test:
-Create a project with a TPageControl
-Create two Pages
-Put a TLabel on each page
-On formcreate set TabSheet1.TabVisible to false;When the program is running the tab shown is the second, but the contents are from page 1.
(Windows XP 32 bits)
