Prevent Pages from breaking web link at slash
I fixed it by:


Clicking on the link; pressing escape at the resulting window; then pressing the left arrow to move to the beginning of the link...
In the Format pane, under Text, on the Layout tab, changing the Indent values to zero.


The Indent values were defaulting to 0.5 in for 'First' and 'Left'. Changing the 'First' value was enough to move the text correctly.