Safari Networking Process causes overheat

Safari/Preferences/Advanced - enable the Develop menu, then go there and Empty Caches. Quit/reopen Safari and test. Then try Safari/History/Show History and delete all history items. Quit/reopen Safari and test. You can also try try Safari/Clear History…. The down side is it clears all cookies. Doing this may cause some sites to no longer recognize your computer as one that has visited the web site. Go to Finder and select your user/home folder. With that Finder window as the front window, either select Finder/View/Show View options or go command - J. When the View options opens, check ’Show Library Folder’. That should make your user library folder visible in your user/home folder. Select Library./Caches/com.apple.Safari/Cache.db and move it to the trash.

Go to Safari Preferences/Extensions and turn all extensions off. Test. If okay, turn the extensions on one by one until you figure out what extension is causing the problem.

Safari Corruption See post by Linc Davis

The problem may be due to Safari extensions or third party plug-ins.

From the Safari menu bar click Safari > Preferences then select the Extensions tab. Uninstall one extension at a time, quit and relaunch Safari to test.

If it's not an extensions issue, try troubleshooting third party plug-ins.

Back to Safari > Preferences. This time select the Security tab. Deselect: Allow plug-ins. Quit and relaunch Safari to test.

If that made a difference, instructions for troubleshooting plugins here.

From the Safari menu bar, please select

Safari ▹ Preferences... ▹ Security

and uncheck the box marked

Warn when visiting a fraudulent website

Test.

Please open the iCloud preference pane and uncheck the box marked Safari. Test. Then check the box again, if you wish. Post the results of the test.

Linc: I also turned off Safari in iCloud preferences, restarted Safari, and it also had no effect. "Safari Networking" is still over 100%, the fan is running at high speeds, and Safari is very slow.