If you find that PDF files you download are not opening in Adobe Reader, but in something like Kami or a website, here are some steps you can try.

Kami settings

At the time of writing, there is an option in the Kami settings that will automatically import all PDF files downloaded.

1. Open Kami, either by clicking the icon in your browser toolbar or by going to web.kamihq.com.
2. Click your profile picture in the upper right of the page, then click Settings.
3. Scroll down a bit and, under the Settings section, make sure Automatically load files in Kami is unticked:

Google Drive settings

If you find that PDFs open in a website (like Kami) when you double-click them in Google Drive, try checking your app settings in Google Drive:

1. Open Google Drive from your bookmarks or by going to drive.google.com.
2. Go to the settings gear in the upper right and hit Settings:

2. On the left sidebar, click Manage Apps.

3. Next to Kami (or any other 'alternative' PDF viewers that open), untick Use by default:

Using the desktop app

If you've followed both steps above, your files shouldn't be opening in Kami or another extension, but may still be opening directly in Chrome.  One possible workaround for this is to open the PDF from the File Explorer in Windows or Finder in macOS, but you can change how Chrome handles this directly like so:

1. Download a PDF file if you haven't done so recently, so it appears under the Downloads icon.

2. Right-click the file under your downloads, then select Always open with system viewer:

This makes Chrome follow the default app setting in Windows or macOS, which should default to Acrobat on GOAL devices.