Slava: USING: ui threads ; [ ui ] in-thread ! ...and then move the new window across the previous. ! C+n does not trigger the fep. ! Also, the above line doesn't work in Windows with a fuel ! listener. I have to type USE: ui ui to get the ui without ! placing it in a thread. .s .r .c below Error in thread 68 (Thread, [ ~array~ ~quotation~ ~quotation~ dip call ]): Generic word layout-state>> does not define a method for the POSTPONE: f class. Dispatching on object: f [ init-catchstack dup 2 setenv slip -> wait-to-return ] [ [ call ] dip -> ] [ 4dup handle-wm-paint -> DefWindowProc ] handle-wm-paint relayout-1 layout-state>> object=>layout-state>> no-method throw [ 63 getenv error-thread set-global continuation -> error-continuation set-global rethrow ] The die word was called by the library. Unless you called it yourself, you have triggered a bug in Factor. Please report. Starting low level debugger... Basic commands: q -- continue executing Factor - NOT SAFE im -- save image to fep.image x -- exit Factor Advanced commands: d -- dump memory u -- dump object at tagged . -- print object at tagged t -- toggle output trimming s r -- dump data, retain stacks .s .r .c -- print data, retain, call stacks e -- dump environment g -- dump generations card -- print card containing address addr -- print address containing card data -- data heap dump words -- words dump tuples -- tuples dump refs -- find data heap references to object push -- push object on data stack - NOT SAFE code -- code heap dump READY .s ==== DATA STACK: # 15 0 0 f f T{ generic.standard:no-method f accessors:layout-state>> } READY .r ==== RETAIN STACK: T{ compiler.codegen:callback-context } READY .c ==== CALL STACK: [ continuations.private:init-catchstack kernel:dup 2 kernel.private:setenv kerne l:slip compiler.codegen:wait-to-return ] 4 1e6e743 61063d0 [ [ kernel:call ] kernel:dip ] 1 11cce2b 5e593b0 [ shuffle:4dup ui.windows:handle-wm-paint windows.user32:DefWindowProc ] 1 157816b 6081170 ui.windows:handle-wm-paint f 1535a63 63d5630 ui.gadgets:relayout-1 f 145e503 62597a0 accessors:layout-state>> f 14c7923 6263490 object=>layout-state>> f 149bd33 62722e0 generic.standard:no-method f 1353ec3 6183410 kernel:throw f 11c2f5b 6183c90 continuations:rethrow f 11c24c3 5e77080 [ threads:self threads:error-in-thread threads:stop ] 1 11cb243 63bf4b0 error-in-thread/tuple-dispatch-engine f 14cd683 632b330 READY