New to ubuntu, new to Libre Office 
It seems like when I enter 2000 for example it always returns to 999,9.
Is this the maximum font size in LibreOffice Impress?
Thanks!
As it looks in my tests, 999.9 is the maximum size for a font.
Why should it be bigger? At 999, a letter protrudes far beyond a normal A4 page. What do you want to do?
Thank you for your answer…
I used to work with powerpoint to make logos or produce pdfs for larger documents or applications/productions, and needed bigger fonts sometimes, around 2-3000 size…
Now it seems I may have to find another way… 
For me powerpoint was a kind of a canvas for creations, without the complex technicality of photoshop/Illustrator for example…
Just scale your drawings? draw on A6, print on A0
There is a way to use larger characters as long as there are only a few characters.
The processing takes place in Draw.
The desired characters are converted into a curve and then copied into the gallery. From there they can be inserted into any document. The characters are now scalable and can be drawn larger if desired.
Important: in Draw a page can be set to several meters in size (max = 6 x 6 m).
An exact description, see:
Begin there with the title “Video 5”
The videos themselves are unfortunately only in German, but I think it is still clearly shown what is meant.
I wish you success.
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With me Windows 10 Home; Version 1909; 64-Bit | LibreOffice, Version: 6.3.4.2 (x64).
ebot, that was very informative, especially with the introduction to LO videos. That in turn prompted me to wonder if there might be other pages of that type with videos exposing other “gems” of LO, in the same way as this does for the Draw module, Unfortunately, the page wiki.documentfoundation.org/Videos/ is (apparently deliberately) uninformative. In other words, this “Hidden Gems” page is itself a hidden gem. Hoes does one discover such pages?
This is the playlist of all tutorials in German at LibreOffice.
The videos are not hidden, you can also access them from the main LibreOffice-German website:
https://de.libreoffice.org/get-help/neue-seite-2/
Unfortunately, no one has ever found anyone who also creates videos for the English-speaking community.