png: enable to write transparent image with :background#630

Merged

k-okada merged 2 commits intoeuslisp:masterfrom k-okada:png_transparent

Dec 16, 2024

+50-10

Commits on Dec 15, 2024

png: enable to write transparent image with :background
k-okada
committed
.travis.sh : arm64v8/ubuntu:focal takes > 90min. skip test/transparent.l, compile test.
k-okada
committed