I'm seeing issues with Resizing in Lessons when using a two column setup with a checklist.
Steps to reproduce:
1. Create a site and add the lessons tool
2. Select Add Content > Add Text and add some example text
3. Click the Book / Page icon in the top left of text section
4. Click the box next to "Two columns inside this one, text flows between them"
5. Click the + icon on the left column and select add Checklist
6. Add a new checklist and save
7. Now resize the page
The Lessons body should resize and no scrollbar should be needed
Resizing to a smaller browser window starts to present a scrollbar and the lessons body goes beyond the screen. (2column.png)
If you separate the columns into their own sections, this issue does not occur. (separateSections.png)