I run Google PageSpeed Insights on my site, and it reports an issue that is "Avoid serving legacy JavaScript to modern browsers", as below: I have no idea of w
mathematical-typesetting
adafruit-circuitpython
calendarextender
completion-service
emu8086
bindservice
cci
pcregrep
kernel32
sqlite-net-extensions
iphone-sdk-4.0.1
nsdata
sunrpc
entitlements
release-notes
appindicator
pymodbustcp
gradle-3.0
vaadin21
camel-cxf
binary-string
bootstrap-vue
infrastructure-as-code
dependency-properties
crdt
pressed
bounding-box
launch-services
magic-command
unspecified