xdg-terminal fails with kde because the std output of which $terminal is wrongly redirected to /dev/null in terminal_kde(). The patch in attachment fixes this issue.
Created attachment 41780 [details] [review] fix terminal_kde()
fixed in http://cgit.freedesktop.org/portland/xdg-utils/commit/?id=a5fba77b61ce14d23a22064fef0e7ec973fae0ec Note: xdg-terminal is unmaintained and isn't shipped with xdg-utils since 1.0.2.
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