In MS Office, there is a text justification option called "Thai Distributed". The tool-tip says:
Align paragraph to both the left and right margins by adding extra space between each two characters for languages with tone mark and vowel mark.
This creates a document with clean look."
Also, in the documentation folder of writerfilter, one may find this file:
0x2461: extra alignment:
8: justify low
5: justify middle
7: justify high
9: Thai Distribute
It clarifies that there is another alignment mode, "Thai Distribute(d)". Unfortunately, I could not find any mention of this mode in LibreOffice source code and documentation.
Here are some screenshots from this feature in MS Office:
This may also be useful:
Requirements for justification in Thai #19
YouTube: Thai Distributed in Office word is the very important tools for spacing
*** This bug has been marked as a duplicate of bug 154881 ***