Great question. Because we do not know exactly what it is on certain people's browsers that might be impacting it I can't give a definitive answer. However, there are some troubleshooting steps you can attempt to see if it works for you.
1. Try Incognito/Safe mode.
2. Try clearing the cache on the browser. Restart the browser afterward.
3. Look at your extensions and/or plugins on the browser. Try disabling them all, if possible, and see if it corrects the problem. If the problem is fixed, go back and re-enable your extensions/plugins one at a time and see if the issue comes back. If you do find that a certain extension or plugin is causing the issue please let us know what it is so we can look into it as well.
4. Try whitelisting Constant Contact in your computer's security program.
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