@geddi this seems to be a common bug coming into WordPress 5.3. It’s being caused by one of your plugins. If you’re not sure which one, deactivate each plugin one by one until the problem disappears, then you know which one it is. Then you can reach out to that plugin developer for a solution.
Emily, you will need to edit code to fix this. You will need to find the file admin-ui.php in the keyring folder in your plugins folder. wp-content/plugins/keyring/admin-ui.php. And you will need to replace line 48 as detailed above. If you are not comfortable editing code, you will need to ask a web developer to do this for you.
