In version 8 of angular-cli, the build is done 2x. One in es5 and one in es2015.
Is it possible to build only on es2015?
Changing the target to es5, it is done o
You need to add the line defaults and put the word not at the begin of every line below in the file browserlist. For example:
defaults
not > 0.5%
not last 2 versions
not Firefox ESR
not dead
not IE 9-11 # For IE 9-11 support, remove 'not'.
After that you can check changes by the command npx browserslist. It should print nothing.