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## Iframe response timeout

If you get this message in edit view it means that you have hit the response timeout for our editing iframe:

_Preview Unavailable_

_Failed to load the preview within the given time constraints._

The default time to load a preview is 15 seconds. You can increase it by adding `PreviewTimeout` in _appSettings.json_. The value should be in milliseconds.

To set the preview timeout to 20 seconds, add this configuration:

This timeout was added in the _EPiServer.CMS.UI_ 10.2.0 package to solve a bug and make the iframe load more reliable.

## ApprovalStepRoleUserLimit configuration

If you are using large user groups in content approvals, there is a risk of performance issues (and unhappy users) due to the high number of notifications in the system. Therefore, there is an `appSetting` called `ApprovalStepRoleUserLimit`, which triggers a validation warning when an administrator adds a group with members exceeding this setting. It will also limit the amount of notifications sent to the users in the group. The default setting is 100 users per group, but it can be configured in this key: