Failures on staging in ubuntuuitoolkit.tests.components.test_textinput

At one point many tests from ubuntuuitoolkit.tests.components.test_textinput and ubuntuuitoolkit.tests.custom_proxy_objects.test_textfield started failing in staging.

ubuntuuitoolkit.tests.components.test_textinput.CaretTextInputTestCase.test_caret_hidden_if_empty(header):

17:15:09.899 INFO _launcher:373 - Attempting to launch application '/usr/lib/arm-linux-gnueabihf/ubuntu-ui-toolkit/launcher' with arguments '-I /usr/lib/modules /usr/lib/python3/dist-packages/ubuntuuitoolkit/tests/components/test_textinput.header.qml --desktop_file_hint=/home/phablet/.local/share/applications/tmp0b42to5n.desktop -touch' as a normal process
17:15:09.916 INFO _launcher:431 - Launching process: ['/usr/lib/arm-linux-gnueabihf/ubuntu-ui-toolkit/launcher', '-testability', '-I', '/usr/lib/modules', '/usr/lib/python3/dist-packages/ubuntuuitoolkit/tests/components/test_textinput.header.qml', '--desktop_file_hint=/home/phablet/.local/share/applications/tmp0b42to5n.desktop', '-touch']
17:15:13.955 DEBUG _common:45 - Moving to object's globalRect coordinates.
17:15:13.956 DEBUG _uinput:485 - Tapping at: 438,121
17:15:30.944 INFO _launcher:544 - waiting for process to exit.
17:15:30.945 INFO _launcher:567 - Killing process 12693
}}}

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/ubuntuuitoolkit/tests/components/test_textinput.py", line 78, in test_caret_hidden_if_empty
    self._assert_not_visible(objectName=cursorName)
  File "/usr/lib/python3/dist-packages/ubuntuuitoolkit/base.py", line 95, in _assert_not_visible
    self.assertThat(object.visible, Eventually(Equals(False)))
  File "/usr/lib/python3/dist-packages/testtools/testcase.py", line 423, in assertThat
    raise mismatch_error
testtools.matchers._impl.MismatchError: After 10.0 seconds test on QQuickImage.visible failed: False != dbus.Boolean(True, variant_level=1)