66506 Allow futures that resolve to null (incl. Future) in Future/StreamBuilder (cla: yes, framework)

66508 [Docs] [Material] Fix Icons api docs (cla: yes, f: material design, framework, team)

66542 Fix last month not being displayed if last date is selected in DateRangePicker (cla: yes, f: material design, framework, waiting for tree to go green)

66567 Length formatter minor fix (cla: yes, framework, waiting for tree to go green)

66582 Update docs about complex character support (cla: yes, framework)

66596 [Material] Remove opacity from dark theme overlay check (cla: yes, f: material design, framework, waiting for tree to go green)