Safari keeps freezing with a rotating beachball

A Troubleshooting Protocol to Identify Problems or Fix macOS El Capitan or Later

You should try each, one at a time, then test to see if the problem is fixed before going on to the next.

Be sure to backup your files before proceeding if possible.

1. Shutdown the computer, wait 30 seconds, restart the computer.
2. Disconnect all third-party peripherals and remove any support software like drivers and plug-ins.
3. Resetting your Mac’s PRAM and NVRAM
4. Reset the System Management Controller (SMC)
5. Start the computer in Safe Mode, then restart normally. This is slower than a standard startup.
6. Repair the disk by booting from the Recovery HD. Immediately after the chime hold down the Command and R keys until the Utility Menu appears. Choose Disk Utility and click on the Continue button. Select the indented (usually, Macintosh HD) volume entry from the side list. Click on the First Aid button in the toolbar. Wait for the Done button to appear. Quit Disk Utility and return to the Utility Menu. Restart the computer from the Apple Menu.
7. Create a New User Account Open Users & Groups preferences. Click on the lock icon and enter your Admin password when prompted. On the left under Current User click on the Add [+] button under Login Options. Setup a new Admin user account. Upon completion log out of your current account then log into the new account. If your problems cease, then consider switching to the new account and transferring your files to it - Transferring files from one User Account to another.
8. Download and install the OS X El Capitan 10.11.6 Combo Update or 10.12.6 Combo Update or Download macOS High Sierra 10.13.3 Combo Update as needed.
9. Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Reinstall OS X then click on the Continue button.
10. Erase and Install OS X Restart the computer. Immediately after the chime hold down the Command and R keys until the Apple logo appears. When the Utility Menu appears:

1. Select Disk Utility from the Utility Menu and click on Continue button.
2. When Disk Utility loads select the drive (out-dented entry) from the Device list.
3. Click on the Erase icon in Disk Utility's toolbar. A panel will drop down.
4. Set the Format type to APFS (for SSDs only) or Mac OS Extended (Journaled.)
5. Click on the Apply button, then wait for the Done button to activate and click on it.
6. Quit Disk Utility and return to the Utility Menu.
7. Select Reinstall OS X and click on the Continue button.

I too have this issue upon opening Safari. It happens on my iMac AND my Macbook. Not running anything intensive. Just opening Safari triggers it.

I tried disabling all extensions and it still happens. I also cleared all cache and cookies.

I notice that you use Dashlane. I do too. When I de-activate the Dashlane extension, the problem stops. I tried this in Safari Technology Preview as well. The problem is consistent across both browsers with the extension activated.

This looks to be a Dashlane problem. I would recommend contacting them and alerting them to the issue.

Kill Safari when you see that.

Use Activity Monitor to Kill Runaway Processes

Use Activity Monitor on your Mac

Runaway applications can shorten battery runtime, affect performance, and increase heat and fan activity.

wwwwes wrote:

Please address the problem. after 8-10 seconds it will show not responding and then return to normal display.

What are you running in Safari? Safari itself is never that CPU intensive. If there are multiple web pages running with power hungry scripts, then it can report that as coming from Safari. Usually there should be something reporting the actual website URL that's responsible for a large amount of CPU utilization, such as where it says "https://support.apple.com" with your setup.

It could be a webpage or possibly a plug-in.

peerleader wrote:

'using over 100%'

That seems improbable. -- Please Provide a Screenshot (command + shift + 4) and drag it over that activity monitor!

Each CPU core can be responsible for up to 100%. However, I've never really heard of Safari going over 100% before. The CPU load reported on the bottom adds up to 100% though. Add system and user together and it's going to be half of the total %CPU.

I have done it all!!!! I have completely uninstalled, trashed all preferences, uninstalled the extension. Logged out, restarted. Reinstalled from scratch and still the problem persists. NOTHING that you do on your end will make any difference. Dashlane is pretty ignorant of their own bugs.

'using over 100%'

That seems improbable. -- Please Provide a Screenshot (command + shift + 4) and drag it over that activity monitor!

Are you using the Dashlane Extension. I turned mine off and the issue stopped. So, for me, it is an issue that Dashlane has to address.