On Intel systems ArdourCanvas::COORD_MAX (1.7e+307) was rounded
to (gint) -2147483648. gtk+ treats negative window size-requests
as 1px.
However on ARM, COORD_MAX was truncated to +2147483648, gtk+ limits
this to 65535. Most WM/Xwin systems cannot handle windows this large.
It also exceeds the max size of cairo [image] surfaces.
This issue was introduced in a1c67b4ad7
when "natural_size" was removed. Before that change infinitely large
canvas had a natural_size of 2x2 px.
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