Adobe changed how they handle permissions. You can make forms like these savable, you just have to have access to Adobe Acrobat to do it. Open the form in Acrobat the File > Save as Other > Reader Extended PDf > Enable More Tools (includes form fill-in and save) Personally I save this version as something with a slightly different name just to avoid confusion but you don’t have to. Once it’s been saved as an extended reader format it can be edited and the filled out form can be saved. Acrobat isn’t open source or free (although I believe there is a free trial version) so it isn’t an ideal solution but it does work. Good luck!
JC Hammond, Freelance Tech Writer