Use Google Drive (upload PDF, open with Google Docs, edit, download as PDF)
Use LibreOffice Draw (open PDF, edit content, export/save as PDF)
Use PDF-XChange Editor (edit text/annotations, save/export as PDF)
Use Sejda PDF Editor (upload PDF, edit, download)
Use Smallpdf (edit PDF via online editor, download)
Use iLovePDF (edit PDF online, download)
Use PDFescape (edit PDF online, download)
Use DocHub (edit PDF in browser, download)
Use Canva (upload PDF, edit elements, download as PDF)
Use Microsoft Edge (open PDF, add annotations/comments, print to PDF)
Use built-in print-to-PDF after edits (edit in another app, then print/export to PDF)