I was just trying out displacy and encountered a weird error.

I was just trying out displacy and this was my code
import spacy
from spacy import displacy
import en_core_web_md
nlp = en_core_web_md.load()
doc = nlp('I have a ginger cat.')
displacy.serve(doc, style='dep', port=8654)

HOWEVER when it gives the result : Using the 'dep' visualizer
Serving on http://0.0.0.0:8654 ...

.... I OPEN this, and the chrome page displays :

"This site can't be reached
The webpage at ** The webpage at http://0.0.0.0:8654/ might be temporarily down or it may have moved permanently to a new web address.

BUT THEN I MANUALLY OPEN localhost:8654 and it works. Why can't I get results with http://0.0.0.0:8654/

0.0.0.0 is the default host address here, but it's not really a valid address to access in the browser. You could try 127.0.01:8654 and that should work, or the "localhost" solution you provided. You can also explicitely put

displacy.serve(doc, style='dep', port=8654, host="127.0.0.1")

and then you'll get a functional link to http://127.0.0.1:8654

We could also consider automatically rewriting the URL when the default host is used, to make this less confusing.

(FYI - these kind of questions can also be put on the spaCy discussion board, as they're not really specific to Prodigy)

Understood about the spacy discussion forum,