There should be a welcome screen which gives user to choose from either "Default UI" or "MS Office UI" or something else?

I think this will increase the popularity of LibreOffice. And I really want that. I have seen people to choose WPS office instead of LibreOffice only because of the UI. I know that LibreOffice is better than WPS. And in linux it is the best.

This is an enhancement request and as such off-topic here. Please read this Introduction - Feature Request and the information where Feature Requests should go to.

May be you are interested in discussion in bug report / enhancement request tdf#135501 (Check/Search for UI Picker).

Beware of UI’s !!!

What is shown on screen leads you to the “intuitive application control” syndrome. Because features can be activated with buttons, menus, key presses, … you think you master the application.

… and you don’t read the manual !

LibreOffice is not Micro$oft Office and does not pretend to be a drop-in replacement. It is a different application suite addressing the same usage domain(s).

LibreOffice is extensively based on styles in nearly all its components (Writer, Calc, Impress, Draw). This is the key to its power.

Offering a cloned UI will encourage direct formatting (the LO name for manual formatting) which is the cause of trouble when editing sophisticated documents. IMHO a good UI should encourage style use. When working with styles, you don’t need all the buttons and various toolbars. A minimal UI to choose the styles is enough.

But the ability to switch to the more common buttons/tools is needed for the tasks where “decorations” must be added to the main flow (be it in a document, presentation or spreadsheet).

There is already a menu View>User Interface> allowing you to choose your preferred UI. Isn’t this sufficient for you?

For which reason would you force your personal choice on users?

The fact that the UI switch is buried deep at the end of a hierarchical menu is a “quality” for me. It implies that the user has the curiosity to play with the app or read the built-in help if (s)he is too lazy to download the User Guide(s). The is a contorted way to force discovery of the features.

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