Alas, those settings will only apply to one document/template at a time. You may want to adjust the formatting of the style to suit your taste. You can now use your chosen keyboard shortcut. Now, style selection should appear in the upper Shortcut keys pane, and the chosen keyboard combination in the lower Keys pane.

In the Functions pane, select the Hanging indent style.

In the Category pane, scroll down to the bottom, expand the Styles entry and select Paragraph.

This is of course subject to your personal preferences

For hanging indent I would choose keyboard combination Ctrl+ Shift+ H.

You can also redefine a shortcut you are never going to use. “available keypress” is an entry without anything to the right of it in the list.

In the Shortcut keys pane, locate an available keypress (function key or kbd combination).

It may look cumbersome, but it is really not difficult, and you only have to do this once.

The format settings for the style is tied to each document/template, but the keyboard shortcut you assign will be persistent on your system. Smooth workflow, and zero screen real estate wasted. Make a keyboard shortcut to apply that hanging indent style. Once you have done a few pages of a document you might find it easier to change the view of Styles in the side pane from Hierarchical to Applied Styles so you can quickly change to another style. The point of using styles is that you really don’t need to click buttons very often. If you always have hanging indents then set that template as Default (to stop it it being default click File > Templates > Manage templates, right click the template and click Reset default).If you frequently use hanging indents for your Text Body style then make a template, File > Templates > Save as template and use that as the start for your document.See the Organiser tab of the paragraph style. If you use it for every paragraph then you should modify Text Body to have a hanging indent as Text Body is the next style after all headings, horizontal line, etc.If you use Hanging Indent style a few times, it will appear in the drop-down style listing.The chapter on Styles in the Writer Guide is worth spending a little time with.

The Writer Guide and the Getting Started Guide are both very helpful, English documentation | LibreOffice Documentation - LibreOffice User Guides.

I would suggest getting comfortable working with LibreOffice.

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