Created attachment 203603 [details]
A screenshot showing calc after the commit with the red charaters

I'm trying to get into helping fix bugs in Libreoffice.  I built the latest 26.2.0.0 alpha on Oct 28th, and found that a spreadsheet I've been using for years had red characters in every cell with more than one line.  
I built on both Fedora fc43 and Pop!_Os(a derivative of Ubuntu 22.04), both show the same problem.  
  After tracking down which commit first show the red character, I looked briefly at the code in the newly committed file.  I don't know enough about LO internals to have any idea if the new code is bad, or if the new code reveals a longstanding bug. Sorry I can't be of much help here.

Git bisect gives the following 
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graham@dansdesk:~/programming/LO/bad_red_text_in_calc$ cat git.bisect.bad.txt  fa7ed3501e1ee47600b41985b7c5b7f60a6a8b29 is the first bad commit
commit fa7ed3501e1ee47600b41985b7c5b7f60a6a8b29
Author: Armin Le Grand (collabora) <Armin.LeGrand@collabora.com>
Date:   Thu Oct 23 18:35:55 2025 +0200

    tdf#167605 take ClipRegion at OutDev into account
    
    ImpEditEngine::DrawText_ToPosition has to take into account
    if a ClipRegion is set at the target OutputDevice when it
    renders using primitives, this is *not* automatically set
    or taken over when a PrimitiveProcessor is created for that
    target.
    
    This revealed a problem, see comments in
    editeng/source/editeng/impedit3.cxx for a detailed
    description.
    
    Change-Id: Ied2cf3f59d57099e616ebe9969c721f796b4b227
    Reviewed-on: https://gerrit.libreoffice.org/c/core/+/192919
    Reviewed-by: Armin Le Grand <Armin.Le.Grand@me.com>
    Tested-by: Armin Le Grand <Armin.Le.Grand@me.com>

 editeng/source/editeng/impedit3.cxx | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)
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