/usr/share/gps/docgen2/navbutton.tmpl is in gnat-gps-common 5.0-13.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 | @@SET@@ BUTTONWHEREAMI = $1
@@SET@@ BUTTONWHOAMI = $2
@@SET@@ BUTTONHREF = $3
@@SET@@ BUTTONNAME = $4
@@IF@@ @_BUTTONWHEREAMI_@ /= @_BUTTONWHOAMI_@
<a href='@_BUTTONHREF_@'><div class="button2">@_BUTTONNAME_@</div></a>
@@ELSE@@
<i><div class="button2">@_BUTTONNAME_@</div></i>
@@END_IF@@
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