#252 #170 - automating 2 monitors, macOS Retina display

Author: kensoh

README.md

@@ -92,7 +92,7 @@ An element identifier helps to tell RPA for Python exactly which element on the
 
 - :globe_with_meridians: For web automation, the web element identifier can be XPath selector, CSS selector, or the following attributes - id, name, class, title, aria-label, text(), href, in decreasing order of priority. Recommend writing XPath manually or simply using attributes. There is automatic waiting for an element to appear before timeout happens, and error is returned that the element cannot be found. To change the default timeout of 10 seconds, use timeout() function. PS - if you are going to use a Chrome extension for XPaths, use [SelectorsHub](https://chrome.google.com/webstore/detail/selectorshub/ndgimibanhlabgdgjcpbbndiehljcpfh?hl=en).
 
-- :camera_flash: An element identifier can also be a .png or .bmp image snapshot representing the UI element (can be on desktop applications, terminal window or web browser). If the image file specified does not exist, OCR will be used to search for that text on the screen to act on the UI element containing the text, eg r.click('Submit Form.png'). Transparency (0% opacity) is supported in .png images. x, y coordinates of elements on the screen can be used as well. The various functions will handle single / multiple input parameters accordingly.
+- :camera_flash: An element identifier can also be a .png or .bmp image snapshot representing the UI element (can be on desktop applications, terminal window or web browser). If the image file specified does not exist, OCR will be used to search for that text on the screen to act on the UI element containing the text, eg r.click('Submit Form.png'). Transparency (0% opacity) is supported in .png images. x, y coordinates of elements on the screen can be used as well. Notes for visually [automating 2 monitors](https://github.com/tebelorg/RPA-Python/issues/252#issuecomment-844277454), macOS Retina display [issue and solution](https://github.com/tebelorg/RPA-Python/issues/170#issuecomment-843168745).
 
 - :page_facing_up: A further image identifier example is a png image of a window (PDF viewer, MS Word, textbox etc) with the center content of the image set as transparent. This allows using read() and snap() to perform OCR and save snapshots of application windows, containers, frames, textboxes with varying content. See this [image example](https://user-images.githubusercontent.com/10379601/124394598-b59cfd80-dd32-11eb-93bb-68504c91afb9.png) of a PDF frame with content removed to be transparent. For read() and snap(), x1, y1, x2, y2 coordinates pair can be used to define the region of interest on the screen to perform OCR or capture snapshot.