Currently, when not logged-in, if you visit any of the Special:My* pages ( 'Mycontributions', 'MyLanguage', 'Mylog', 'Mypage', 'Mytalk', 'Myuploads') you will see contributions for your IP address.
For wikis with temporary accounts, showing the contributions for an IP address doesn't make sense anymore.
Proposed change: when temporary accounts are enabled, if the user is logged-out, we should require the user to login to access these pages.
Note that If the user is already logged-in with a temporary account, then the Special:My* pages will work just fine as is, without any changes needed.