Moving data from an old google sheet to a new google sheet
My original intend to use a new functionality in google sheets on a sheet I already created with the old version. As I already had a lot of content I didnt want to rewrite everything. And I only wanted to add a few formulas using "COUNTIFS". And copy pasting from the old to the new didnt work.
Here is what did work for me to convert from old google sheet to a new google sheet:
In a spreadsheet created in the old version, click the down arrow next to a sheet tab and click Copy to…, and copy the sheet (and its contents) to a spreadsheet created in the new version.
You may find other solutions here:
Also google needs some versioning because "old" and "new" are not the best keywords to search for.