We Keep Coding

loading pref showConsoleLogs before prefs were initialised, you will not get the correct result

CMS - wordpress
after some changes i have error on one page:
loading pref showConsoleLogs before prefs were initialised, you will not get the correct result content-script.bundle.js:333
http://www.74skazka.ru/restorany/baden-gourmet/?donotcachepage=84523706ac5384c08c3beb52312fdef0
if i delete all code error anyway here

The Ghostery extension causes a similar issue for me, but you didn't include the full logs, so can't be sure

The error itself should be harmless. It is an internal error message that comes from prefs.es, which is used by the Ghostery extension and the Cliqz extension.
There is an open bug report:
https://github.com/ghostery/ghostery-extension/issues/135
Until a fix is released, it is safe for you to ignore the message, as it does not indicate a problem in your website.

Javascript - "Cannot read property 'closingEls' of undefined" and "Script error."

I get the following errors in the JavaScript console with no file source hint:
Uncaught TypeError: Cannot read property 'closingEls' of undefined
and
Script error
These errors prevent my page from running scripts and I don't understand what kind of errors they are.
I tried searching what 'closingEls' is, but no luck. I don't know what type of tags I need to put in this question due to the vague nature of these errors.
Edit 1: Please, before you say show us the code, read the question! my scripts do not run in the first place. And this errors does not come out of the site's scripts, it comes from the user's agent trying to load the page.
Edit 2: Please, advice a way to deal with the users having this errors and can not load the page successfully. I would consider this very helpful, constructive and question-related.

The "Script error." happens in Firefox, Safari, and Chrome when an exception violates the browser's same-origin policy - i.e. when the error occurs in a script that's hosted on a domain other than the domain of the current page.
Can read more over here:
http://blog.errorception.com/2012/04/script-error-on-line-0.html
https://blog.sentry.io/2016/05/17/what-is-script-error.html
Regarding "Uncaught TypeError: Cannot read property 'closingEls' of undefined" Even I'm getting them in my Sentry log, and I don't know how to fix them. I think these errors are from Browser Extensions trying to add their own script. In case of the "Script Error" the extension (or browser) has not allowed you to access the debugging information, while the other extension (or browser) has allowed you to see it.
Most Client JS error tracking ignore "Script Error.". Read here
https://docs.sentry.io/clients/javascript/tips/
http://blog.errorception.com/2012/03/tale-of-unfindable-js-error.html
Let's hope that this question finds popularity and we find the developer of the extension.

Uncaught Error: Expected to find a document already present for removed

When I try to log into app, the error I get in client console (chrome dev tools) is this:
Uncaught Error: Expected to find a document already present for removed mongo.js?69942a86515ec397dfd8cbb0a151a0eefdd9560d:253
and the login is halted: the loading gif from the accounts-google package shows and the loading never ends.
I however get no errors in server console. Unfortunately, the error gives me little understanding as to where to even start debugging my app from.
I have gone through the portion where the error is thrown in the mongo.js file, but I don't get what's going on there from it either.
Since I do not have any idea where I am going wrong, this is the link to the project repository.

Maybe you was use fast-render package and doing 2 subscriptions for the same publication as explined here
Hope this help someone.

Javascript error - extensions::SafeBuiltins:82

Uncaught TypeError: Illegal invocation
Everything works good but I noticed there is an error in console.
Does anyone know what is this?

If you have the same problem with me, try to disable extensions. For example, when I disable "Open SEO Stats", the error message is disappeared.

I am the author of Open SEO Stats. The Page Speed module of Open SEO Stats extension is not working on Google Chrome 44 and causing error message "Uncaught TypeError: Illegal invocation - extensions::SafeBuiltins:82" in console window.
This bug is caused by Google Chrome 44 issue. I have fixed it. You can update the extension to latest version 9.1.0.0.
If you have any questions about Open SEO Stats, you can also send email to pr [at] chromefans.org.
Open SEO Stats in Chrome Web Store: https://chrome.google.com/webstore/detail/open-seo-statsformerly-pa/hbdkkfheckcdppiaiabobmennhijkknn
How to update: http://www.chromefans.org/chrome-tutorial/how-to-manually-update-chrome-extensions.htm

google chrome bug?

this message appears all the time in chrome developer tool's console:
Port error: Could not establish connection. Receiving end does not exist. miscellaneous_bindings:232
chromeHidden.Port.dispatchOnDisconnect miscellaneous_bindings:232
Error in event handler for 'undefined': Cannot read property 'instanceId' of undefined TypeError: Cannot read property 'instanceId' of undefined
at [object Object].<anonymous> (chrome-extension://mgijmajocgfcbeboacabfgobmjgjcoja/content_js_min.js:2:372)
at chrome-extension://mgijmajocgfcbeboacabfgobmjgjcoja/content_js_min.js:1:182
at miscellaneous_bindings:276:11
at [object Object].dispatch (event_bindings:203:41)
at Object.<anonymous> (miscellaneous_bindings:235:27) event_bindings:207
chrome.Event.dispatch event_bindings:207
chromeHidden.Port.dispatchOnDisconnect miscellaneous_bindings:235
is this a bug in chrome or there is something wrong in my chrome installation?

It seems to be a problem with the Google Dictionary (by Google)
This script doesn't seem to exist or is not accessible by that port.

Based on some googling, this is a problem with a chrome extension, but it may not be clear which. (For me, it was Feedly).
The quickest way to find out which is causing the problem:
Disable all your chrome extensions. (Chrome menu > tools > extensions)
Refresh a page - hopefully the port error should be gone now
Re-enable your extensions one by one, refreshing the page after each, 'til the error pops up again in the console. You should now have your culprit.
I know this could be a pain if there are a lot of extensions :/ personally, I took it as a chance to prune the unused / unworthy extensions while I was going through them.