Error message when opening firefox in LInux

[halek]

I am trying to get up to speed using FireFox or Iceweasel on the Raspbian OS on a Raspberry Pi computer.

Any time time I open either program using the terminal I get the following error message.
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(process:14888): GLib-CRITICAL **: g_slice_set_config: assertion 'sys_page_size == 0' failed
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Can any one advise me what adjustment I need to make to avoid this message?