I realized a substantial data discrepancy between an amount of monitored HTTP requests in Chrome Developer Tools and some of web based website performance monitoring/scoring tools, like gtmetrix or webpagetest.
The discrepancy is weird for me, cause all of used web based tools are showing the same requests amount, but Developer Tools are showing an amount, which is twice bigger. The related website data is in Developer Tools twice bigger too. I realized those behaviour on different sites, but as an example you could look into these:
The requests amount is 60-65, Developer Tools shows 130. I compared all requests as HAR files and realized, that webbased tools and Chrome Developer Tools are loading partly different files: webbased tools are loading 10 unique files, which aren't loaded by Developer Tools, Developer Tools are loading 60 unique files, which aren't loaded by webbased tools.
The main question is: why is it so?
