When viewing a Google Sheets in a mobile browser you have handy filter buttons at the top.
How do I display the mobile version of the page in a desktop (preferably Firefox) browser?
I seek to display only Google Sheets that way while displaying non-mobile versions of other websites at the same time. So changing the UA globally won't work.
I found a solution through some URL tweaking: changing the document link URL from
docs.google.com/spreadsheet/lv?key=... displays the spreadsheet with the desired filter buttons. The "list view" mode can also be toggled from the view menu in spreadsheets when logged in.