Adding links in different paragraphs raises a TypeError

[davide-targa]

Using the buildout included with the egg with python3.7.

To replicate the issue:

1. Start plone instance and creare a new site;
2. Upload a file (I used the pdf in the ‘test’ folder);
3. Add a new page with two paragraphs;
4. Link a word of the first paragraph to the file and save the page.

A TypeError is raised:

2020-06-15 15:31:35,284 ERROR   [plone.app.textfield:86][waitress] Transform exception
Traceback (most recent call last):
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/plone.app.textfield-1.3.2-py3.7.egg/plone/app/textfield/transform.py", line 62, in __call__
    encoding=value.encoding)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/Products.PortalTransforms-3.1.7-py3.7.egg/Products/PortalTransforms/TransformEngine.py", line 173, in convertTo
    usedby=usedby, **kwargs)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/Products.PortalTransforms-3.1.7-py3.7.egg/Products/PortalTransforms/chain.py", line 49, in convert
    data = transform.convert(orig, data, **kwargs)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/Products.PortalTransforms-3.1.7-py3.7.egg/Products/PortalTransforms/Transform.py", line 202, in convert
    return self._v_transform.convert(*args, **kwargs)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/plone.outputfilters-3.1.2-py3.7.egg/plone/outputfilters/transforms/html_to_plone_outputfilters_html.py", line 33, in convert
    res = apply_filters(filters, orig)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/eggs/plone.outputfilters-3.1.2-py3.7.egg/plone/outputfilters/__init__.py", line 7, in apply_filters
    res = filter(data)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/src/collective/outputfilters/enhancelinks/enhance_links.py", line 200, in __call__
    self.process(data)
  File "/home/davide/sites/collective.outputfilters.enhancelinks/src/collective/outputfilters/enhancelinks/enhance_links.py", line 186, in process
    raw_html += tail
TypeError: can only concatenate str (not "bytes") to str