Can I do something for the Android platform (part of the browser / webkit) to run my own predefined JavaScript (scripts) along with every webpage viewed by the default Android web browser?
There is no single "standard Android web browser."
I don’t know how to install custom scripts in AOSP browser or in Chrome. There are third-party applications, such as TamperMonkey , which are actually their own web browser and offer custom scripts, while other third-party browsers may have hooks that can be used for the GreaseMonkey equivalent.
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