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How Do I Fill Out A PDF If It’s Not Fillable By Default?
Either make a copy of the file before filling it in so the original is always preserved or add a button to SAVE AS. There is (as far as I know) no simple way to stop it writing over the original if the user presses SAVE. Possibly you could write some Javascript (attached to a button) that would do a Save As and then close the PDF without saving - but that still wouldn’t stop the user from simply pressing File > Save.
Fill out PDF: All You Need to Know
The button is on that page in Photoshop > Plugins: Here's the result (the screenshot has all the background and white border erased for a better understanding): If you've ever looked at screenshots before, that sort of looks like a photo editing app (especially the white borders) but the way you can change the background (in black, you can see the Photoshop logo) makes it look more like the result of some sort of app. ___________________________ What you can do If you want to restore this page to the original, just get a backup of the original file, which has the “BACKUPS FOR BULK FILES PLEASE” box checked, then copy the PDF to its original location. Here's the full link on the page: File > New > PDF Backup.