Creating of the multiple issues with TGE grids from the same page is unsupported
Jira allows creating an issue in a fullscreen mode.
To enter fullscreen mode click on the "Create" button on the top navigation bar with "Ctrl"/"Cmd" button pressed. It will open a new tab with issue creation form. On the same page you can click "Create" button again and open "Create Issue" popup. Thus JIRA allows to create an issue while you are creating an issue