Uncaught exeption when trying to use unserialize

[izzy]

With the test text

a:2:{i:0;s:4:"pleh";i:1;a:2:{i:0;s:4:"pleh";i:1;R:3;}}

The unserialize function will throw the following exception

Error in event handler for contextMenus: SyntaxError: Unknown / Unhandled data type(s): r
at error (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1000:61)
at _unserialize (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1109:18)
at _unserialize (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1098:35)
at _unserialize (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1098:35)
at D3.unserialize (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1115:25)
at menu.onclick (chrome-extension://gncnbkghencmkfgeepfaonmegemakcol/js/D3.js:1256:54)

This exception should be handled and at least known types should be printed. "R" (for recursion) could be printed as simple text like "recursion pointer".