How to fill out and sign a PDF on a Chromebook, for free
School and government PDFs that will not open in the Chromebook viewer, and the way around it.
Chromebooks open PDFs in the Gallery or Chrome viewer, which handles simple forms. Many school and government PDFs are built for Adobe Reader instead, so you see a blank page that says "Please wait... If this message is not eventually replaced" or the boxes simply do nothing.
Those files use a format called XFA that only desktop Acrobat reads. Many of them also carry a normal form underneath. Open the file at bettrpdf.com/fill: it drops the XFA layer, shows the regular form, and lets you type, sign with your touchpad or touchscreen, and download. If yours is XFA-only, you will see the same "Please wait" page here; ask the sender for a standard PDF, or fill it on any Windows or Mac computer with Adobe Reader.
Nothing is installed, it works on school-managed Chromebooks that block extensions, and downloading is free with no account. If the form is a scan with no boxes, click anywhere on the page to add text.