Features request: Don't show window until remote file fully downloaded; Mouse's right-click/Quit option.

System:    Host: Linux-1 Kernel: 5.4.0-72-generic x86_64 bits: 64 Desktop: Cinnamon 4.8.6 
           Distro: Linux Mint 20.1 Ulyssa 
Machine:   Type: Desktop System: MSI product: MS-7885 v: 1.0 serial: N/A 
           Mobo: MSI model: X99S SLI PLUS (MS-7885) v: 1.0 serial: N/A UEFI: American Megatrends 
           v: 1.F2 date: 06/13/2019 
CPU:       Topology: 6-Core model: Intel Core i7-5820K bits: 64 type: MT MCP L2 cache: 15.0 MiB 
           Speed: 1335 MHz min/max: 1200/3600 MHz Core speeds (MHz): 1: 1267 2: 1201 3: 1201 
           4: 1201 5: 1201 6: 1200 7: 1200 8: 1200 9: 1409 10: 1201 11: 1200 12: 1200 
Graphics:  Device-1: NVIDIA GM204 [GeForce GTX 970] driver: nvidia v: 460.73.01 
           Display: server: X.Org 1.20.9 driver: nvidia resolution: 3840x2160~60Hz 
           OpenGL: renderer: GeForce GTX 970/PCIe/SSE2 v: 4.6.0 NVIDIA 460.73.01 

xviewer --version
Xviewer 2.8.3

Issue

When showing a remote image, it would be nice if 'xviewer' could wait until the whole file has been downloaded before showing its window.
I'd like a mouse's right-click/Quit option.

I usually use a browser add-on to open Url images with 'xviewer', in full screen. Currently 'xviewer', sometimes (depends on the server the remote file is in), opens its 'full screen' window before there is a whole image file to show. Its (whitish) window covers the browser (the whole screen) for several seconds while the image file is downloaded.

I open an image (browser) link by mouse's right-clicking on the link. It would be nice to be able to exit 'xviewer' by right-clicking/Quit. Currently I first have to exit full screen, by double clicking on the image centre, and then click on 'xviewer's window's X to exit (I want to do everything with the mouse).

Steps to reproduce

Open remote file in a slow server: 'xviewer' hides everything in the desktop until the remote file is fully downloaded.

Mouse's right-click: No 'Quit' option. :-(

Expected behaviour

Open remote file in a slow server: 'xviewer' waits until the remote file is fully downloaded and then shows it.

Mouse's right-click: There is a 'Quit' option. :-)

linuxmint / xviewer

Features request: Don't show window until remote file fully downloaded; Mouse's right-click/Quit option. #139