Failed to load .map resources in default themes folder

Software Support
#1

Hello,

I cannot figure out why I am getting the following errors in my browser console consistently, even after the last 3 updates—and in each case I made a clean install:

[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (popper.js.map, line 0) 
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (dropdown.js.map, line 0) 
[Error] Failed to load resource: the server responded with a status of 404 (Not Found) (util.js.map, line 0)

I have tried to locate the files; they do not exist. The errors point to the following directory(s): plugins/themes/default/js/lib/bootstrap/ and plugins/themes/default/js/lib/popper/

Details:

Many thanks for any help you can provide.

#2

Adding “.map” to the popper.js , dropdown.js and util.js files in the themes>default>js>lib>bootstrap/popper folders makes this problem go away.

#3

How I do that, please?

#4

Edit the DefaultThemePlugin.inc.php file.

#5

Hello, I have the same warning.

I uncommented the line below in “… \ js \ lib \ popper \ popper.js”:
sourceMappingURL = popper.js.map

But now the error appears:
popper.js? v = 3.2.1.2: 2449 Uncaught ReferenceError: popper is not defined at popper.js? v = 3.2.1.2: 2449

If you completely delete the line “sourceMappingURL = popper.js.map” the warning and error disappear.

Can I remove that line?

Thanks.

#6

Hi everyone, these errors will not effect your site in any way. The .map files are only used for development purposes. Do not rename the popper.js, dropdown.js or util.js files or you may cause problems with your site.

#7

On the last line of the above-mentioned .js files, just remove the # after the //. This will do it and the .map files will not be accessed.
I do this usually on child themes that I derive from the default theme (but not on the original default theme).