Request for help: iMAC (21.5 inch version: 10.10.5) incompatible with FIREFOX

[lagoa2]

HELP REQUEST: iMAC (21.5 inch, Late 2009) - OS X, Yosemite, version: 10.10.5. -This is the last version. SAFARI works well, but I use little. The MOZILLA / FIREFOX that has recent software, started to give a few problems, the worse problem is: DO NOT LOAD the PDFs. What is the other BROWSER compatible with this iMAC ????
I want to uninstall FIREFOX, and install another compatible BROWSER. Thank you so much.

 

[ferrarr]

Why not upgrade OS X to El Capitan (10.11)?

 

[pm-r]

Why not upgrade OS X to El Capitan (10.11)?

Or, it looks like they could go right up to "Maximum MacOS: X 10.13.x*" but I wouldn't suggest that with that iMac model:
https://everymac.com/systems/apple/...uo-3.06-21-inch-aluminum-late-2009-specs.html

Or try using the existing Safari as it supports "LOADING PDFs". But personally, we found Yosemite gosh awful to use.






- Patrick
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