Set as default image viewer

[ashkanRmk]

How can I set it as my default image viewer in linux?
It doesn't appear in application list to open images with it.

[octipus]

In windows 10 setting it as default works by right-clicking on the image file, Open with > Choose another app > More apps >Look for another app in PC. However, i set the app as the default app for images but when i open an image it actually opens the app without adding the picture to it. I have to drag and drop the picture to the app in order to see it.
Would be nice to work straight away when i double click on a picture.

Otherwise, the app is great! lightweight and minimal for a fresh modern look. Good job

[imagicalFantasy]

I've the same issue... without this, the program don't have any utility.... :(

[ashkanRmk]

No i want this on Linux .. :(

[sgtskips]

For people looking how to set it as default viewer i found this but it seems like lightviewer doesn't load the image i open it with is there a particular param or something i can do ?
https://itsfoss.com/add-application-list-open-applications-ubuntu-1310/