I searched for "refresh" and got multiple pages returned. When I click on "page 8", I get a very large error (only the first few lines are shown):

Warning: count(): Parameter must be an array or an object that implements Countable in _filter_url() (line 536 of core/modules/filter/filter.module).

_filter_url('I have now managed to customise the toolbar of the 'ItemEditor' thank you, however the drop down boxes for the CSS sheet and the HTML styles are both empty.  ', Object) (Line: 42)
Drupal\filter\Plugin\Filter\FilterUrl->process('I have now managed to customise the toolbar of the 'ItemEditor' thank you, however the drop down boxes for the CSS sheet and the HTML styles are both empty.  ', 'en') (Line: 118)
Drupal\filter\Element\ProcessedText::preRenderText(Array)
call_user_func_array(Array, Array) (Line: 101)

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