Sometimes Excel document contains information at the beginning of the worksheet and after that, it contains some count of empty (blank) columns. In case, if the number of empty columns is considerably huge, the rendering time increases and hence, it affects the performance.
To skip rendering of empty columns GroupDocs.Viewer Cloud provides RenderEmptyColumns property, which allows omitting to render empty columns as shown in the sample below.
API Usage There are steps that usage of GroupDocs....Annotation Product Solution GroupDocs...Advanced usage / Rendering options by document type / Rendering...