The Properties side pane only offers a part of the wealth of formatting options available in the various dialogs. To be concise, the options are presented as “shortcuts” to most frequent values under the form of drop-down menus (in which you obviously enumerate only a few values).
In the dialogs where a dimension can be freely entered, measurement are presented initially in the default units for your locale or as set in Tools
>Options
, LibreOffice Draw
>General
, Unit of measurement.
But this setting does not preclude the use of another unit. You noticed that the unit is part of the text box. If you enter a number without unit, the default unit is used. If you explicitly specify a unit as pt, in, cm, mm, …, it overrides the default unit.
In you case, if you see 0.1 cm
, replace it with 1 pt
and you’re done.
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