Minor bug and UI fixes (#6729)

* PLT-6797 - Code block language tag not selectable

* PLT-6771 - Aligning search box with RHS

* PLT-6827 - Fixing link color in error bar

* PLT-6241 - Adding edge detection

webapp/sass/layout/_headers.scss

@@ -426,6 +426,7 @@
 .app__body {
 
     .channel-header__links {
+        display: inline-block;
         font-family: 'Open Sans', sans-serif;
         font-size: 22px;
         height: 30px;