update README

Author: emilykl

README.md

@@ -106,13 +106,10 @@ conda install jupyter anywidget
 ### Static Image Export
 
 plotly.py supports [static image export](https://plotly.com/python/static-image-export/),
-using either the [`kaleido`](https://github.com/plotly/Kaleido)
-package (recommended, supported as of `plotly` version 4.9) or the [orca](https://github.com/plotly/orca)
-command line utility (legacy as of `plotly` version 4.9).
+using the [`kaleido`](https://github.com/plotly/Kaleido)
+package (version 1.0 or greater).
 
-#### Kaleido
-
-The [`kaleido`](https://github.com/plotly/Kaleido) package has no dependencies and can be installed
+Kaleido has minimal dependencies and can be installed
 using pip
 
 ```
@@ -125,6 +122,12 @@ or conda
 conda install -c conda-forge python-kaleido
 ```
 
+Kaleido requires Chrome or Chromium to generate images. By default, Kaleido will use the Chrome or Chromium version already installed on your system. If you don't have it installed or Kaleido can't find it, you may need to install it by running the command:
+
+`plotly_get_chrome`
+
+on your command line.
+
 ## Copyright and Licenses
 
 Code and documentation copyright 2019 Plotly, Inc.