My old eyes can’t read my entries, imported from and old version. I need to change the global font to make them legivle.
I assume you’re asking for the Writer component.
Open Tools>Options, LibreOffice Writer>Basic Fonts (Western). There you can choose a font face for various contexts and an associated size.
Be aware, though, that it modifies default definition of paragraph styles. That’s OK for new documents. If styles in existing documents have been modified in any way, these modifications have precedence over the new default. You can reset to the new default by reloading the styles from a new document. See the built-in help on how to proceed.
However, it will work never on old documents only if you applied direct formatting, i.e. you formatted “manually” your document from toolbar buttons or strokes like CTRL+B.
As a last resort, some OSes or video drivers offer a magnifying glass feature. For example, the nouveau driver for nVidia cards under Linux has commands Windows++ or Windows+- for zoom in and zoom out respectively. Both left and right Windows key can be used.
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