Small spreadsheet extremely laggy

[FreSch]

Good day, this is a really odd issue that has been driving me up a wall.
Basically, a family member complained to me that his spreadsheet was really slow, and basic actions such as adding a new row caused excel to freeze up for a good 10-15 seconds. Here’s what I tried:

Windows + excel (the original file)
windows + libreoffice
linux + libreoffice
creating a new excel sheet and copying data across, without formatting
creating a new odt sheet and copying data across, without formatting

All of them resulted in slow performance, lags, and crashes. I have no clue why this keeps happening for a small spreadsheet that doesn’t even go past row 210.

The spreadsheet was used to track buying and selling stocks, so I’ve edited the document to remove any information. The lag remains, however. Anyone know what’s causing this?
Here are both an xlsx and odf version.
censored.2026.xlsx (301.1 KB)
censored.2026.ods (137.9 KB)

[Lupp]

The sheet from the .xlsx file contains hundreds of dummy images (“pictures”) which can’t be opened/shown/interpreted by LibreOffice (and possibly also not by some versions of Excel).
Pasting a complete copy of a sheet from that source With Paste Special ... into a new LibO Calc document WITHOUT OBJECTS should solve the problem.

[FreSch]

Gave it a try, and indeed, that seemed to have fixed the issue. Really weird as I remember pasting stuff without formatting when moving to a new document, but it somehow didn’t work. Oh well.
Still don’t know where these objects even came from, but what matters is that the problem is resolved now. Thanks so much!

[Lupp]

Formatting wasn’t the cause, imo.

[PKG]

@Lupp

into a new LibO Calc document WITHOUT OBJECTS should solve the problem.

Or you can double-click an image (select it in the Navigator (F5)), then press Ctrl+A to select all images in the document, and finally delete them all using the Delete key.