Change Default PDF Program for Microsoft Edge
To change the default program for PDFs to stop the PDF crashing issue isn’t within Microsoft Edge. You will need to adjust the default for Windows.
Download Adobe Acrobat Reader DC from Adobe - Download Adobe Acrobat Reader
If you have it, skip to Step 3
Once it downloads, install it
In the search bar at at the bottom-left of the screen, type in “default” and select “Default Apps”
Select “Choose default apps by file type”
Scroll down to .pdf, and select “Adobe Acrobat Reader DC” as the default