PDF Manager

About

PDF Manager is a complete PDF-building workspace that runs entirely inside your
  browser. Combine PDFs, pull out just the pages you need, add images and text,
  put everything in the exact order you want, and export a clean new PDF - without
  uploading a single file to anyone.

  WHY YOU'LL WANT IT
  Most "merge PDF" and "split PDF" tools make you upload your documents to a
  website you don't control. That's a problem when the file is a contract, a
  payslip, a medical record, an ID, or anything else you'd rather not hand to a
  stranger's server. PDF Manager does all the work locally, so your documents
  never leave your device. It's also fast, works offline, and has nothing to sign
  up for.

  WHAT YOU CAN DO
  - Merge several PDFs into one.
  - Pick and choose individual pages - take page 3 from one file and pages 1-2
    from another.
  - Reorder pages by dragging them into place.
  - Drop in images (PNG, JPEG, WebP, GIF) and plain text as new pages.
  - Duplicate or remove any page, and preview the result as you build it.
  - Export with the quality you need: print quality, a smaller web-friendly file,
    or a heavily compressed version for email.

  HOW IT WORKS
  Open the full-page workspace from the toolbar icon (or the right-click "Open PDF
  Manager" menu). Drag your files into the Source pane, then drag the pages,
  images, or text you want into the Destination pane. For multi-page PDFs, select
  several pages at once and drag them in together. Arrange the order, choose an
  export profile, and click Export - your finished PDF downloads instantly.

  PRIVATE BY DESIGN
  Everything - reading, rendering, assembling, and exporting - happens on your
  computer. PDF Manager makes NO network requests, asks for NO access to the
  websites you visit, and collects NO data, analytics, or tracking. The only
  permission it requests is a right-click shortcut to open the app. Close the tab
  and everything is cleared from memory.

  OPEN SOURCE
  PDF Manager is free and open source (MIT licensed). You can read the full source
  code, verify exactly what it does, report issues, or contribute on GitHub:
  https://github.com/lucianhanga/chrome.extension.manage.pdfs

  PERFECT FOR
  Combining scanned documents, building a single PDF from mixed files, extracting
  a few pages to share, assembling an application or portfolio, shrinking a PDF
  small enough to email, or reordering a report - all privately, all in your
  browser.

  Free, no account, no uploads. Learn more:
  https://github.com/lucianhanga/chrome.extension.manage.pdfs/blob/main/docs/user-guide.md