The URL bar in iOS shrinks / expands on scrolling causing change
in height. This triggers our resize handler and forces user to
jump to the selected message. This jump triggers before our
keep pointer in view logic kicks in which means user scrolls back
to the previous selected message instead of scrolling forward.
To fix this, we only do this jump when width changes on mobile
devices.
Note that modern devices support resizeable windows of all forms but
for most use cases where app is full expanded, this seems like the
right fix.