As of Bitwarden Version 1.26.0, the Bitwarden 1PIF and 1Password CSV import doesn't work very well. The URL does not map correctly. Therefore, no logins will pop up when you use the extension.

Bitwarden Import documentation: https://help.bitwarden.com/article/import-data/

*update 2018-05-16 - 1Password export includes an escape character for "". So passwords that have \ in it will show up as \

Workaround

  1. Export from 1Password as Tab Delimited Text (CSV could also work, but the below python code would need to be modified)
import pandas as pd
import pandasql

from pandasql import sqldf
pysqldf = lambda q: sqldf(q, globals())

df = pd.read_csv('pw.txt',sep="\t",quotechar='"')
#Could probably do the below with pandas, but my SQL skills are better than pandas.
psql = ("""
          SELECT   'Logins' as folder
                  ,null as favorite
                  ,'login' as type
                  ,title as name
                  ,notes
                  ,null as fields
                  ,url as login_uri
                  ,REPLACE(username,'\\\\','\\') as login_username
                  ,REPLACE(password,'\\\\','\\') as login_password
                  ,NULL as login_totp
          FROM  df
      """)
finaldf = pysqldf(psql)
finaldf.to_csv('pw.csv',index=False)
  1. Import into Bitwarden as 'Bitwarden (CSV)'