Update documentation

Author: mdmintz

examples/visual_testing/ReadMe.md

@@ -1,4 +1,4 @@
-<p align="center"><a href="https://github.com/seleniumbase/SeleniumBase/"><img src="https://seleniumbase.io/cdn/img/sb_logo_f6.png" alt="SeleniumBase" width="330" /></a></p>
+<p align="center"><a href="https://github.com/seleniumbase/SeleniumBase/"><img src="https://seleniumbase.io/cdn/img/sb_logo_f6.png" alt="SeleniumBase" width="445" /></a></p>
 
 ## [<img src="https://seleniumbase.io/img/logo6.png" title="SeleniumBase" width="32">](https://github.com/seleniumbase/SeleniumBase/) Automated Visual Regression Testing
 

help_docs/how_it_works.md

@@ -31,9 +31,9 @@ class TestMFALogin(BaseCase):
         self.enter_mfa_code("#totpcode", "GAXG2MTEOR3DMMDG")  # 6-digit
         self.assert_text("Welcome!", "h1")
         self.highlight("img#image1")  # A fancier assert_element() call
-        self.click('a:contains("This Page")')
+        self.click('a:contains("This Page")')  # Use :contains() on any tag
         self.save_screenshot_to_logs()  # In "./latest_logs/" folder.
-        self.click_link("Sign out")  # Must be "a" tag. Not "button".
+        self.click_link("Sign out")  # Link must be "a" tag. Not "button".
         self.assert_element('a:contains("Sign in")')
         self.assert_exact_text("You have been signed out!", "#top_message")
 ```