Compound class names are no longer supported.
What you may do instead is attempt using CSS selectors.
In your case, the following line of code should help you get the element you want :
el3 = driver.find_element_by_css_selector(".action-btn.cancel.alert-display")
It finds the element with all three classes (action-btn, cancel and alert-display) in the class attribute.
Do note that the order of the classes doesn't matter here and any of the classes might appear anywhere within the class attribute.
As long as the element has all 3 classes, it'll be selected.
If you want the order of the classes to be fixed, you can use the following Xpath:
el3 = driver.find_element_by_xpath("//*[@class='action-btn cancel alert-display']")
I hope this resolves the issue!
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