Unfortunately there are a lot of unprofessional people in open source, and while I hate to stereotype, they are especially prevalent in the JavaScript community where it's typical to have hundreds to thousands of unknown dependencies in every project. What can be done? I don't know. (Before I'm labeled as entitled -- I spend a lot of time on open source, without the unprofessional behavior.)
Maybe not looking at code one includes in a product has become much too common practise, but if some library for a button (funny I never felt the need to use one) includes special stylings on special days and you included it, that is on you. Sure it would have been nice of them to point this out if they didn't, but after all you are taking someone elses code for a button so you should know what it does.
And what whith the whole being "professional" as a value system, which I fear has often to be taken in the very narrow USofA centric PoV ?
I can't relate to the sentiment that everything has to be aseptized in order to conform to a very strict and dehumanized, bland and sfw (aka professional), just to cater to the work environment culture of a few.
If in your freetime you don't like something coming from an open source project that doesn't owe you anything, don't use/associate. If you don't like it in your work place, there's a reason you're paid I guess? Or change job, or do an internal fork.
Many frontend projects have 100s of deps, and while that’s a separate problem, imagine if a large fraction of them spammed bandwidth and console output with this.
Some logo or ASCII art in some/most of those deps would hardly be the real issue.
Worse, you sound new and square. In the olden times such "easter eggs" or cool logos were welcome, and in the DOS days (but also in the Unix console) often included ASCII art.
Which library is this? Couldn't find it via a quick Google.
If it's free and open source? Well if you don't like it you are welcome to apply for a refund.
Probably not that common knowledge, or we'd have libraries designed for outputting nice log/admin interface data to the console XD
Edit: There it is - https://github.com/MattCozendey/doom-console-log