Created attachment 103715 [details] Small example where cell format string is not preserved on LO re-open. Lubuntu 14.04 with up-to-date repo LO. The attached file was created by entering 202100083 in A1 and setting the cell format string to "00\.00\.00\.000\.0" (without quotes) then saving as xlsx. When it's reopened in LO, the format string is changed to "00.00.00.000.0" (without quotes). I'm pretty sure that whatever's happening is happening during the LO open operation, since the format string looks fine in the XML and e.g. is imported fine by EPPlus. Also tested on a separate Windows 7 Excel 2013 installation, and the format was preserved there on reopening. Does not occur with ods.
Confirmed under GNU/Linux x86_64 using v4.2.5.2. Status set to NEW. Platform to All. Minor amendment to summary.
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