Zabbix

.......... [DEV-4828] fixed Selenium tests after z-textarea-flexible was introduced in multiple frontend fields

* commit '04232b26937a7835ebc08379d35cb471478bdbd0':
  .......... [DEV-4828] fixed overwrite method and added missing data source after review
  .......... [DEV-4828] fixed minor coding style issue
  .......... [DEV-4828] fixed the selector of the element that should be removed from screenshot before assertion
  .......... [DEV-4828] fixed checking for wrong attribute in Selenium test
  .......... [DEV-4828] fixed element tag in Selenium test
  .......... [DEV-4828] fixed undefined method call in preprocessing behavior as well as fixed a couple of tests
  .......... [DEV-4828] fixed another part of failing Selenium tests
  .......... [DEV-4828] removed unneeded commented line
  .......... [DEV-4828] fixed another part of failing Selenium tests
  .......... [DEV-4828] fixed entering values in z-textarea-flexible elements in multiple Selenium tests
  .......... [DEV-4828] removed temporary fix for focus removal from page
  .......... [DEV-4828] added CTextareaFlexible element and added temporary fix for removeFocus method