Why a Is Single doctype giving error when sending mail ?
Traceback here:
Traceback (most recent call last):
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/app.py", line 61, in application
    response = frappe.handler.handle()
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/handler.py", line 21, in handle
    data = execute_cmd(cmd)
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/handler.py", line 56, in execute_cmd
    return frappe.call(method, **frappe.form_dict)
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/__init__.py", line 1026, in call
    return fn(*args, **newargs)
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/core/doctype/communication/email.py", line 75, in make
    comm.insert(ignore_permissions=True)
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/model/document.py", line 221, in insert
    self._validate_links()
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/model/document.py", line 731, in _validate_links
    invalid_links, cancelled_links = self.get_invalid_links()
  File "/home/frappe/benches/bench-2019-03-01/apps/frappe/frappe/model/base_document.py", line 471, in get_invalid_links
    values.name = doctype
AttributeError: 'NoneType' object has no attribute 'name'
Is it actually possible to send mail from is_single doctypes or not or there’s some bug ??