(npviewer.bin:4411): Gdk-ERROR **: The program ‘npviewer.bin’ received an X Window System error.
This probably reflects a bug in the program.
The error was ‘BadMatch (invalid parameter attributes)’.
(Details: serial 249 error_code 8 request_code 140 minor_code 3)
(Note to programmers: normally, X errors are reported asynchronously;
that is, you will receive the error a while after causing it.
To debug your program, run it with the –sync command line
option to change this behavior. You can then get a meaningful
backtrace from your debugger if you break on the gdk_x_error() function.)
*** NSPlugin Wrapper *** ERROR: NPP_HandleEvent() wait for reply: Connection closed

対策としては、mozillaサイトの公式ビルドを使うと、問題なく表示出来ました。google chromeでもきちんと表示出来ますが、カスタマイズが限られるので小生は公式ビルドのfirefoxを入れています。