How can I change the widget width?

The app has an option to change the width of the widget. These options can be found in the app preferences page in the 'Visual styles' section on the left side panel:

You can type the desired width or leave it empty for an unlimited width (it will take the width of its parent container):

In the screenshot below, you can see an example of a widget with a maximum width:

If we reduce the size to 200 pixels, the widget will now look like this screenshot: