First, a brief caveat: I offer the following information with no guarantee what implications, if any, it has upon your security. I doubt that it does, but it's prudent that I still note this.
That said, this is how you would do it within the TAILS os, The file path may be different in your specific case, but the general approach will likely be the same.
Alright, I'll throw my hat in the ring.
This is an act of purely passive-aggressive coding.
First, we read in words from dictionaries (only using words that contain valid onion values), then we use those words to construct a tree. Each "branch" is a comparison, so if the word starts with 'h', we create an 'h' branch from the root, then and 'e' branch from '...
The Tor Browser Bundle overwrites your local files in every update. This is intentional.
I recommend to save your personal homepage in a directory outside of TBB's directory and make a link. So you only have to renew the link. Another possibility is to import the file on each update.