Even before, wider tables were breaking out of the content area, but after the page tools were made sticky, this problem became significantly more problematic, as these tables will now overlap the menu. This is possible, because the content is later in the dom than the menu, because tables size to content and because grid allows elements to overflow outside of the allocated grid space.
Generally wide tables are not at the top of the page, so if the tools are not sticky, you won't encounter this problem.
I added the following for myself to get this somewhat workable, but... it's a bit of a mess.
/* Fix wide tables on narrow layout */ @media all and (max-width:999px) { /* table overflow protection */ .wikitable { display: block; overflow-x: auto; /* table border collapse no longer functions, so remove border */ border: 0; /* The background of the table can now be outside the table, so restore original */ background-color: unset; } .wikitable > thead, .wikitable > tbody, .wikitable > tfoot { /* Cancel out floating table headers, as this is now within another scroll context */ top: 0 !important; /* Apply the background color here, as no longer on table */ background-color: #f8f9fa; } } /* Fix wide tables on pages with tools menu */ @media all and (min-width:1000px) and (max-width:1399px) { /* table overflow protection */ html.client-js.vector-feature-page-tools-pinned-enabled .wikitable { display: block; overflow-x: auto; /* table border collapse no longer functions, so remove border */ border: 0; /* The background of the table can now be outside the table, so restore original */ background-color: unset; } html.client-js.vector-feature-page-tools-pinned-enabled .wikitable > thead, html.client-js.vector-feature-page-tools-pinned-enabled .wikitable > tbody, html.client-js.vector-feature-page-tools-pinned-enabled .wikitable > tfoot { /* Cancel out floating table headers, as this is now within another scroll context */ top: 0 !important; /* Apply the background color here, as no longer on table */ background-color: #f8f9fa; } }