This JavaScript error happened right after I clicked on mark as read in the popup:
```lang=json
{
"errorMessage": "TypeError: sourceModel is null",
"url": "https://pt.wikipedia.org/w/load.php?debug=false&lang=pt&modules=ext.echo.controller%2Cdm%2Clogger%2Cui%7Cext.echo.styles.badge%2Cnotifications%7Cext.echo.ui.desktop%7Cmoment%2Coojs-ui-core%2Coojs-ui-widgets%7Coojs-ui-core.styles%7Coojs-ui.styles.icons%2Cicons-alerts%2Cicons-content%2Cicons-interactions%2Cicons-user%2Cindicators%2Ctextures%7Cschema.EchoInteraction&skin=vector&version=4377d2b7cb99",
"lineNumber": 8,
"columnNumber": 808,
"errorObject": {}
}
```
in debug mode I get this:
```lang=json
{
"errorMessage": "TypeError: sourceModel is null",
"url": "https://pt.wikipedia.org/w/extensions/Echo/modules/controller/mw.echo.Controller.js?d173b",
"lineNumber": 487,
"columnNumber": 3,
"errorObject": {}
}
```
{F4218123}