Another sample might be related to this bug, search "1634005027" takes ~1min while MS Excel completes almost instantly
test.ods (application/vnd.oasis.opendocument.spreadsheet), 1.29 MB, created by Ｖ字龍(Vdragon) on 2017-08-11 09:37:30 UTC
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Creator: Ｖ字龍(Vdragon)
Created: 2017-08-11 09:37:30 UTC
Size: 1.29 MB

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Attachments on bug 108347: 134074 | 135449 | 135486