Basically, when an alert is popped up in javascript, I can dismiss() it from python perfectly OK, by calling selenium.webdriver.common.alert.Alert(browser).dismiss().
However, if the "browser user" dismisses the alert by clicking [OK] (on screen) with their mouse, then the browser alert gets "Lost in Space" the body.text can no longer be accessed from python.
So... How do I recover the "text" from the page originating the alert, esp after the human user has clicked [dismiss] on the page's alert?
Here are the hints and a script to demonstrate the problem...
FYI: The objective of the originating code is it allow the browser user intervene on screen in testing and manually response to specific alerts.
#!/usr/bin/env python
import os,sys,time
import selenium.webdriver
import selenium.webdriver.support.expected_conditions
print dict(python=sys.version,selenium=selenium.__version__)
path=os.path.join(os.getcwd(),"hello_worlds.html")
url="file:///"+path
open(path,"w").write("""<HTML>
  <HEAD><TITLE>Head Title</TITLE></HEAD>
  <BODY><H1>Hello, worlds!</H1></BODY>
</HTML> """)
browser=selenium.webdriver.Firefox()
browser.get(url)
body=browser.find_element_by_tag_name("body")
print "BODY:",body.text
try:
  for enum,world in enumerate("Mercury Venus Earth Mars Asteroids Jupiter Saturn Uranus Neptune".split()):
    if "Earth" in world: world+=": So do MANUALLY dismiss! {Click [OK] now!!!}"
    else: world+=": AUTO PILOT... please DONT dismiss! {done via selenium.dismiss()!}"
    browser.execute_script('alert("Hello, %s!")'%world)
    if selenium.webdriver.support.expected_conditions.alert_is_present():
      print selenium.webdriver.common.alert.Alert(browser).text
    time.sleep(enum+5)
    if "Earth" not in world: selenium.webdriver.common.alert.Alert(browser).dismiss()
    print "BODY:",body.text
finally:
  browser.quit()
Output: (Crash at Earth)
{'python': '2.6.6 (r266:84292, Aug 18 2016, 15:13:37) \n[GCC 4.4.7 20120313 (Red Hat 4.4.7-17)]', 'selenium': '2.53.2'}
BODY: Hello, worlds!
Hello, Mercury: AUTO PILOT... please DONT dismiss! {done via selenium.dismiss()!}!
BODY: Hello, worlds!
Hello, Venus: AUTO PILOT... please DONT dismiss! {done via selenium.dismiss()!}!
BODY: Hello, worlds!
Hello, Earth: So do MANUALLY dismiss! {Click [OK] now!!!}!
BODY:
Traceback (most recent call last):
  File "./js_alert.py", line 37, in <module>
    print "BODY:",body.text
...
selenium.common.exceptions.UnexpectedAlertPresentException: Alert Text: Hello, Earth: So do MANUALLY dismiss! {Click [OK] now!!!}!
Message: Unexpected modal dialog (text: Hello, Earth: So do MANUALLY dismiss! {Click [OK] now!!!}!) The alert disappeared before it could be closed.
The strange thing is that if the browser user triggers another alert (on another page even!), then a selenium.dismiss() will pull body.text back from limbo and selenium with from then will operate as per (my) expectations.
Any suggestions on how to get the browser back to the page.body?  (And escape the alert)
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