This is because both Mozilla and Google have removed support for NPAPI plugins. Netscape Plugin Application Programming Interface and it is the API that we have used to create our browser plugins for both Chrome, and Firefox. Microsoft Edge (Windows 10 and later) does not support any kind of plugin at all. Due to these factors, it is impossible for us to provide any solution for these browsers.
As such, we cannot continue to develop or support our browser plugins, until such a time as we are presented with a viable alternative; both Mozilla and Chrome (PPAPI) offer alternative API's that can be used, but these are either too limiting, or too unstable, and do not allow us to create a plugin for a complex PDF Editor that would suit the needs of our users and ourselves.
*Note: Internet Explorer is still available and still supports ActiveX plugins such as ours. Because of this, we will continue to support our IE plugin until such a time as Microsoft stops supporting ActiveX plugins.
**Note: Firefox no longer supports NPAPI plugins.Opera is now based on Chrome's source and, as such, no longer supports the use of NPAPI plugins.
Use the only browser that we are able to support, Internet Explorer, which is available and installed by default on all windows PCs.
At the time of writing, we are looking into a possible "open in PDF-XChange" function for select browsers. This would not allow you to view PDF files directly within your browser using our software, but would instead send a link to the document from the web browser directly to our installed application, allowing us to open it directly without a browser in use. There is no timeline currently available for when we may offer this.