Report line/column numbers in the output

Report line/column numbers associated with error/warnings where appropriate.

(This SO question and answer might be useful to get started: https://stackoverflow.com/questions/49018783/element-startindex-is-undefined-when-using-withstartindices-option-in-cheerio.)

Start by locating the code that produces error and warning output, then investigate whether Cheerio's withStartIndices option provides the needed source positions, as described in the linked Stack Overflow question. Done means reporting line and column numbers for errors and warnings wherever appropriate.

Written by the indexing model from the issue text.