Spreadsheets extremely slow to load in LibreOffice Calc 6.4

I upgraded recently from LibreOffice 6.3 to 6.4. I’m finding that spreadsheets take forever to load, in some cases 10 minutes or more. These should load in seconds. The load time seems directly proportional to the size and complexity of the spreadsheet in question.


Background information:

OS Is Linux Mint 64 18.3 (Mate), basic system spec is Core i3 6100U, 4GB RAM.

On another laptop with a less powerful Pentium n3710, but same RAM and OS, there is no delay in loading. That is running Office 6.2.8., as I’ve not gotten around to upgrading it to 6.3 yet.

The issue seems specific to XLS files, which (for historical and compatibility reasons) is what I generally use. I re-saved the largest spreadsheet in ODS, and that then loads in Calc 6.4 with no delay. [THIS IS WRONG, SEE BELOW]

UPDATE(2): The issue is not the file format, but how the spreadsheet is loaded. Loading the spreadsheet from within Calc is now extremely slow, regardless of the format. This is the case whether the spreadsheet is chosen via File → Open, or from the list of recently opened Libre Office documents.

But launching the spreadsheet from within Caja file manager, the load is near instantaneous. The same is true by choosing a spreadsheet from Places → Recent Documents on the main Linux menu. However, if Calc is already open, then the loading process by either of these methods is extremely slow.

Please test with a clean profile Menu/Help/Restart in Safe Mode

I’ve tried restarting in safe mode, and accepting the default settings offered. In this mode, the first file or two loaded very quickly but after that Calc reverts to an ultra-slow load for subsequent files.