change chat from a sidebar to a column (#3113)

* change chat from a sidebar to a column

Using a 2-column layout prevents the chat scrollbar from overlapping the page
scrollbar. Also, it no longer needs to calculate extra padding for elements.

* remove unused Sidebar.tsx

* fix css for chat column

* re-center "Go to last message" button

* main content column always uses maximum height

* lint

* re-hide scrollbars in mainContent on chromium

* fix chat column width when input is over-full

* chat is only fixed-width in desktop

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Co-authored-by: janWilejan <>

web/components/ui/Footer/Footer.module.scss

@@ -1,8 +1,6 @@
 @import '../../../styles/mixins';
 
 .footer {
-	position: absolute;
-	bottom: 0;
   display: flex;
   align-items: center;
   flex-flow: row wrap;