Doubling of file extension when exporting a frame

[ua-knight]

The file extension ".png" is doubled when exporting a frame.

Steps to reproduce the bug

1. Export a frame using "Single frame as a PNG file"
2. If the sprite has the title "MyTitle", the frame is exported with the filename "MyTitle-1.png.png"

Environment details

• operating system: Windows 10
• browser (or offline application version): Chrome

Sprite details

• number of frames: 1
• sprite resolution: 32x32
• session duration: 0? (doesn't know what this means)

[TheOnlyTruMe]

I have experienced this same issue on many exports