SharePoint 2019
Summary
The modern experience of SharePoint is available for SharePoint Online and SharePoint 2019.
To add some features for this environments, the only way is to use SharePoint Framework.
Current behavior
If the .sppkg file is installed on a SharePoint Online environment, it works great but when the package is installed on a SharePoint 2019, this one does not work.
Expected behavior
Be able to install the package on SharePoint Online AND SharePoint 2019 (On-Premise).
Additional information
To be able to install the solution on SharePoint Online and SP2019 On-Premise, the features of the solution are limited.
It is necessary to build a new version of the SharePoint package and reuse the code.
A lot of tests must be performed on both environment to ensure the solution works great on both of them.