[Bug] Recent/Sample Data panel cannot be turned back on

[lanselin]

The check box "Don't show Recent/Sample Data panel again" cannot be turned on again. Once the box is checked, the sample data disappear, but they cannot be turned on again. There needs to be a check box to allow this in the interface without the sample data.

Instead, the interface has "Data Source Overview/Help" and "Select Encoding", which do not seem to be relevant options.

[lixun910]

As a workaround, there is an option in Preference to turn the "Sample Data Panel" back on in the current version:

This will be fixed in #2462:
Show "Don't show Recent/Sample Data panel again" checkbox when it has been checked, so that user can uncheck it and toggle the sample data panel.