recently a new major version of Gisquick plugin compatible with QGIS
version 3 has been released. Please install the most recent version
2.0.1 or update already installed version 2.0.0 to new 2.0.1.
Unfortunately version 2.0.0 contains critical bug which avoids
publishing a project.
Please test version 2.0.1 and report possible issues on GitHub .
On behalf of Gisquick development team, Martin Landa