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| Using | Plugin | Math Formulas | Inline Editing | Works in Mobile | Auto-numbering | Comment |
|---|---|---|---|---|---|---|
| Yes | To Test | CelesteCS Math |  | Looks promising... | ||
| No | Bob Swift Advanced Tables |
| | | | Like the most but requires math functionality. |
| Yes | Excellentable | | |  | (as far as I can tell) | Nice search function but ugly. |
| No | Spreadsheets for Confluence | | | | | n/a |
So far all these are pretty limiting.
How about embedding google spreadsheet into the page and see if it can be edited live?
Yes this generally works with some limitations, but not for Corporate Websites.
Encryption
Looks promising, no public key, but simple enough - https://marketplace.atlassian.com/plugins/com.prcpo.confluence.plugins.secure-content-block
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