Unity Web Player not working?

I’ve been working on this little first person system just for fun (and possibly for any game I may need that needs an FPS system) and I’ve been experimenting with a lot of things. I decided to try exporting it to Unity Web Player. I checked the box “Offline Deployment” since I wasn’t planning on putting it on any website. I double-clicked the html file. Firefox comes up and it has the Unity setup and all. But this is what I got instead

I understand that the Unity Web Player is deprecated and is no longer supported by future unity updates, but have they actually fully disposed of it? Should I use the WebGL export instead?

This may be a bit irrelevant, but in a way, it could answer my question by using an alternative. I just checked to see if I downloaded the module to export to WebGL, it said I didn’t, which isn’t surprising. I clicked on “Open Download Page” and it said “Page not found.” Where would I download the WebGL module?

Found my answer. I was doing offline deployment, which was fine. However, I had Development Build checked. I unchecked that and now I can play my game with the Unity Web Player. I can’t decide between WebGL and Unity Web Player. WebGL doesn’t need any plugins, however, Unity Web Player looks a lot better in terms of shading and quality. Also, to get the WebGL module, I simply opened the Unity Download Assistant, unchecked everything except WebGL, and installed it.