When in the Database Browser the Data tab is read only, leaving it not possible to edit the data or insert/delete any records from the icons displayed at the bottom of the Grid tab.
To apply change per table:
Click on the red circle icon at the bottom left corner of the data grid to turn it to green. If icon remains red, click on the down arrow icon next to the red circle . Click on the arrow down of the Update Columns to ensure all are checked and click OK to close window.
To apply change to all tables:
1. Select Tools | Options menu option
2. Select Grid under Environment from left side tree
3. Uncheck "Show data as read-only" located at the bottom-right corner and hit OK.
