Created attachment 204107 [details]
The example file in Impress, its PPTX version in PP and Impress

This is related to bug 169524

If the ODP attachment 204073 [details] gets saved to PPTX and reloaded, the textbox gets a bit less high.

1. Open attachment 204073 [details]
-> In the sidebar, notice that the textbox height is 16.84 cm
2. Save as PPTX, open in PP
-> In the sidebar, the textbox height is also 16.84 cm - good!
3. Open the PPTX in Impress
-> The text flows out of the box, the textbox height is 16.59 cm (0.25 cm smaller...).
4. Save the PPTX again, reopen in Impress
-> Now the textbox height is 16.34 cm (0.25 cm smaller again)
5. Open the saved PPTX in PP
-> The textbox height is 16.59 cm

So there is a bit of height loss upon each reload, compounding with each save.

This started in 25.8, but before it was automatically fitting the height, which may or may not have been better:

commit 620b89adea77519fd5d057cac7e1acf8a6fb2544
Author: Balazs Varga <balazs.varga.extern@allotropia.de>
Date:   Thu Mar 6 13:29:07 2025 +0100

    tdf#165321 - sd ooxml import fix missing shapes or shapes with near
    
    zero height