Operating systems

Your iMac (21.5-inch, Late2013) cannot be upgraded beyond macOS 10.15.7 Catalina.

If you are having trouble connecting to and using websites with your older version of Safari, try it with a newer third party browser that is still being updated to meet current internet security protocols.

I suggest you take a look at Firefox browser or Brave browser.

Download an alternative browser and install it into your Applications folder. Launch and use that when you encounter websites that don't play well with Safari.

The highest compatible macOS version, is relative to the year model of the iMac.

To identify your iMac model, go to Apple on the menu bar and select About This Mac

Then open > Identify your iMac model - Apple Support and scroll down the page to your model.

tractable wrote:

my iMac (21.5 in, late 2013) is version 14.3 with OS Catalina 10.15.7

Nope sorry, Catalina is the highest macOS that a Late 2013 iMac can run.

No way to know because you have not told us what model year of iMac you have.

click here ➡️ macOS 10.15 Catalina is compatible with these computers - Apple Support

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