3043241 - Loading the Fiori Launchpad or Fiori Launchpad Designer login resources (JavaScript, CSS...) fail with 500 Internal Server Error

• Fiori Launchpad Fiori Launchpad Designer login has a blank page, and errors can be seen in the F12 console log, loading resources (JavaScript, CSS...) fail with 500 Internal Server Error. i.e.
  
  abap.js:2 Failed to load resource: the server responded with a status of 500 (Internal Server Error)
  X.send @ abap.js:2
  main.html:1 Uncaught (in promise) Error: failed to load 'sap/ui2/shell/shell.js' from /sap/public/bc/ui2/**path**/shell.js: 500 - Internal Server Error

• Following error shows in F12 dev tool trace content part:
  "Message E 00 156 cannot be processed in HTTPS plug-in mode".
• In work process level 2 dev trace with Task Handlder & ICF components, below error recorded:
  
  H HTTP> ab_HttpErrorHandler (role: 2, protocol: 2, error: Log on with a dialog user)
  ... ...
  H HTTPS> [1] ab_HttpCleanUpExt: Message E 00 156 cannot be processed in plugin mode HTTPS
  
  
• In dev_icf trace shows error "Log in with a dialog user".

• Fiori Launchpad
• Fiori Launchpad Designer
• SAP Gateway

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