Unexpected error in "experiment[prepare].instruction[prepare]" while running the begginer tutorial

Hi, I've just tried to run my first experiment (the begginer tutorial) and I get an error. Is it happening in the instruction block? I don't know how to debug this. The instruction block is just a form_text_display.

I'm using opensesame (3.2.1+b1-1) in Ubuntu 16.04.

This is the message:

Stopped

The experiment did not finish normally for the following reason:

Unexpected error
Details

item-stack: experiment[prepare].instruction[prepare]
exception type: AttributeError
exception message: 'Visual' object has no attribute 'set_surface'
time: Wed Mar 21 18:57:05 2018
Traceback (also in debug window)

  File "/usr/lib/python2.7/dist-packages/libqtopensesame/misc/process.py", line 154, in run
    exp.run()
  File "/usr/lib/python2.7/dist-packages/libopensesame/experiment.py", line 439, in run
    self.items.execute(self.var.start)
  File "/usr/lib/python2.7/dist-packages/libopensesame/item_store.py", line 102, in execute
    self.prepare(name)
  File "/usr/lib/python2.7/dist-packages/libopensesame/item_store.py", line 142, in prepare
    self[name].prepare()
  File "/usr/lib/python2.7/dist-packages/libopensesame/sequence.py", line 124, in prepare
    self.experiment.items.prepare(_item)
  File "/usr/lib/python2.7/dist-packages/libopensesame/item_store.py", line 142, in prepare
    self[name].prepare()
  File "/usr/share/opensesame_plugins/form_base/form_base.py", line 178, in prepare
    rowspan=rowspan)
  File "/usr/lib/python2.7/dist-packages/libopensesame/widgets/_form.py", line 402, in set_widget
    widget.set_rect(self.get_rect(index))
  File "/usr/lib/python2.7/dist-packages/libopensesame/widgets/_widget.py", line 144, in set_rect
    self._init_canvas_elements()
  File "/usr/lib/python2.7/dist-packages/libopensesame/widgets/_label.py", line 101, in _init_canvas_elements
    x=x, y=y, max_width=w, html=self.html).construct(self.canvas)
  File "/usr/lib/python2.7/dist-packages/openexp/canvas_elements.py", line 37, in construct
    return cls(canvas, *self._args, **self._kwargs)
  File "/usr/lib/python2.7/dist-packages/openexp/_canvas/_richtext/richtext.py", line 64, in __init__
    Element.__init__(self, canvas, **properties)
  File "/usr/lib/python2.7/dist-packages/openexp/_canvas/_element/element.py", line 71, in __init__
    self.prepare()
  File "/usr/lib/python2.7/dist-packages/openexp/_canvas/_richtext/xpyriment.py", line 38, in prepare
    self._stim.set_surface(surface)
AttributeError: 'Visual' object has no attribute 'set_surface'