I am working on a writer document and i would like to switch to calc spreadsheet to create a table and copy and paste it into the writer document. I want to do this without closing any of calc or writer
Usually the ALT+TAB key allows you to easily switch between your open programs without closing them.
If you want to create a new spreadsheet document:
File | New | Spreadsheet will open a new empty spreadsheet in a new window.
If you want to use an existing spreadsheet:
File | Open and navigate to the required document will open the existing document in a new window.
In both cases, if you have an open Writer document, it will still be available unless you close it.
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