Error: "this is undefined" & html-minifier-terser deleted something major, cannot proceed.

[FranGomezVenegas]

Hi All,

I migrated one existing project to use open-wc recently and then I'm in the way to generate my first build/dist.

When I run the project by npm start from the code then everything works fine but when I try to create my first build then I have 6 lines with the message "html-minifier-terser deleted something major, cannot proceed." and two other issues about "error: this is undefined".
This is happening in two components that are not part of my development but imported, google-chart and ua-parser

As example, in ua-parser it indicates that the problem is caused by the "this" on this line: )(typeof window === 'object' ? window : this);

I tried to deploy it in my webserver and then it has 3 errors when trying to load the same js file, and this js file starts by this: "const e="undefined"!=typeof window&&null!=window. ...."

I read https://rollupjs.org/guide/en/#error-this-is-undefined but found no way to fix the problem for this this is undefined issues.

For html-minifier-terser deleted something major, cannot proceed. I found no reference anywhere and even I don't know which is the object that causes this error.

Please, any useful info on how to handle those stoppers would be really appreciate and welcome.

Thanks in advance
Regards,