So here is the scenario: You have your water boiling and the teabag in your mug. You pour the water and oops, the string is pulled into your cup. I found an easy way to stop that from happening. Here is all you have to do.
Step 1. Tear a vertical slit in the teabag envelope lid.
Step 2. Slid the string into this tear.
Step 3. Fold the envelope closed leaving the string to hang out.
Step 4. Hang your teabag in your cup like you normally would and pour your water. The added weight of the envelope will keep the water from pulling the string into your cup.
If you have a teabag that is not attached to the envelope simply insert the tag inside and then follow steps above.