Reduce Cypress docker image size

I'm running UI tests using Cypress with their docker image cypress/browsers:node12.6.0-chrome75. Unfortunately the size of the image is about 1.1GB, which is slowing my tests down quite a bit.

Any way to reduce this, or are there smaller images available?

This is my docker file:

FROM cypress/browsers:node12.6.0-chrome75

WORKDIR /opt/app

COPY ./.npmrc /opt/app/.npmrc
COPY ./package.json /opt/app/package.json
COPY ./yarn.lock /opt/app/yarn.lock
RUN yarn

COPY . /opt/app/

ENTRYPOINT ["yarn"]
CMD ["build"]