Windows 10 v1903 build 18362.476, Kingsoft Spreadsheets 9.1.0.4550, Inkscape 0.92.
From the spreadsheet I am going file>export to pdf. It appears to be PDF-1.7. I also notice that when I check the properties of the pdf when opened with Inkscape, it unsurprisingly I suppose doesn't use US swop coated ICC profile which I suspect is needed. If I change its properties to use that profile, save & close Inkscape & reopen the file, it is no longer using the US web coated profile. Inkscape saves it as PDF-1.4
Attached is a one page sla file with the table in question just plonked anywhere. Thanks for your attention, doing my head in a bit.
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