Report Generator: follow dynamic link, return kills columns width

Steps to reproduce:

• use a doctype with a dynamic link field
• open report generator
• make sure link doctype and link name are selected
• click on a link name
• after the linked document has opened, click return in the browser
• observe the grid: column width is now from the content width and not a proper grid

Expected behaviour:

• grid remains the same

Workarounds:

• click F5
• open link in new tab