When your Defects page won't load or gives "Whoops, we hit a snag" error, it is usually due to a corrupt filter setting which prevents the board from loading. Filters are saved as a Preference on a per-user basis. To clear the potentially corrupt filter setting, you can delete the filter preference. Each user experiencing this issue will need to walk through the process to clear their own preference.
Release : SAAS
Component : AGILE CENTRAL
On your dashboard or a custom page, add the "Custom HTML" app from the App Catalog.
Paste the Preference Deleter code from this URL into the HTML section of the Custom HTML app. and <Save>.
You will be prompted to enter the Preference Name, enter: data-table-default/-200044
Make sure there are no beginning or ending spaces in the entry and click Find Preference.
For each preference that is found, please click the Delete button and confirm Delete Preference Permanently.
Once you have deleted all preferences, click the Find Preference button again and ensure that you see a popup box titled Preference Not Found.
Logout immediately (don't navigate to any other page, so as not to save any additional preferences).
Now when you login the filter is gone from the Defects page and should load.