I’m using LibreOffice in conjunction with Ubuntu 14.04LTS on an ACER Aspire One, and I keep my system up-to-date. LibreOffice Calc seems to have a particularly difficult time opening XLSX files, even when they’re less than 250kB. I’m talking LONG, like an hour or so. The application screen goes gray, and any other CALC window is frozen as well. Once I save the file in ODF format, I can get in and out of the file quickly… but I truly dread opening Excel files. This has been a long-standing problem for me - like a year or so. I’d hoped it would get fixed with update releases, but it hasn’t happened.
[edit: added ubuntu14 tag]
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