I just wanted to add that for “icu-libs” package, some environment variables need to be set.
RUN apk add --no-cache \
msttcorefonts-installer \
fontconfig \
ttf-dejavu \
ttf-droid \
ttf-freefont \
ttf-liberation \
icu-libs
# Update font cache
RUN update-ms-fonts && fc-cache -f
# Set environment variable for .NET to use ICU
ENV DOTNET_SYSTEM_GLOBALIZATION_INVARIANT=false
ENV LC_ALL=en_US.UTF-8
ENV LANG=en_US.UTF-8