[Bug] Gifski encoder resets second frame duration to 20ms for 2-frame GIFs

Describe the bug When encoding with gifski, if the GIF contains only two frames, the duration of the second frame becomes invalid. Attachment 1 is a GIF generated using the gifski encoder, where the second frame flickers noticeably. When editing it again in StG (ScreenToGif), it shows that the duration of the second frame has been reset to 20ms. Attachment 2 is a GIF generated using the KGy encoder, which works normally. My current tests indicate that this bug only occurs with 2-frame GIFs; 3-frame GIFs work fine. A temporary workaround is to duplicate the second frame and halve their durations.

To Reproduce Steps to reproduce the behavior:

1. Record a gif with 2 frame
2. Set time to 1000ms each
3. Save and watch

Expected behavior 2 frame, display 1000ms each

Screenshots Attachment 1: gifski

what it looks like before saving what it looks like when edit the result gif

Attachment 2: KGy (perfect working)

Desktop (please complete the following information):

• OS: Windows 10 x64
• Version 2.43.2

Additional context Add any other context about the problem here.