Created attachment 185683 [details]
Page style with vertical writing mode
The page style in the attached document is set to "Right-to-Left (vertical)". That is the writing mode suitable for texts in East Asian scripts.
All places relevant for the text box are set to style:writing-mode="page" in the file markup.
Open the file. Error: The text in the text box is horizontal. The text should be vertical, see the linked part of the ODF spec.
The API shows TextWritingMode="LR_TB" and WritingMode="0", corresponding to the wrong rendering.
A text box is able to render vertical text. There even exists a predefined text box for vertical text. So the problem is not the rendering itself, but the fact that vertical rendering is not used.
repro with Version: 188.8.131.52.alpha0+ (X86_64) / LibreOffice Community
Build ID: 7a7eb4aa21ca0c83db825fe8d5a5278611b391d8
CPU threads: 4; OS: Linux 5.15; UI render: default; VCL: gtk3
Locale: cs-CZ (cs_CZ.UTF-8); UI: en-US