Multiple installation of Tags in Google Tag Manager [closed]

Question

I am wondering how to deal with multiple installation of Google Tag Manager and how to work with another Tags.

So I am kinda new in this topic and need some guidance on beggining. I am using Google Tag Assistant Legacy extension to check if everything works correctly. On home page when I check extension it shows 5 tags:

1. Global site tag (gtag.js)
2. Google Ads Remarketing Tag
3. Google Analytics
4. Google Tag Manager
5. Google Tag Manager (with the same ID as in previous).

Extension shows "Multiple installation of Google Tag Manager detected" error.

I have been reading about soulution on the Internet and so far I checked developer tools -> Network -> write down "gtm.js" in search bar and reload page and only one record shows in the window. But page on which I am working regarding to my knowledge is not a single page application as some poeple says. So is "Multiple installation" real error or should I just ignore it? And how to check if this might cause any problem.

And I have question also to other tags. To be sure if I think correct - Global site Tag should be deleted? I don't know why should I have this one if I have GTM? I want to have all tags implemented via GTM. Also Google Ads Remarketing Tags should be deleted because I have this Tag already in GTM. Am I right?

How can I check whether some data are sending doubled? And I have another problem - this set is for home page and some other subpage but I have also pages that contains (by Google Tag Assistant Legacy) this Tags:

1. Global site tag (gtag.js)
2. Global site tag (grag.js) (but with different ID then the first one)
3. Google Ads Remarketing Tag
4. Google Analaytics
5. Google Tag Manager

So the question is why now I have only 1 Google Tag Manager by two different Global site tag. I have not idea how could I tidy it up so any suggestion will be much welcomed.

Answer 1

1. Don't rely on the extension. Open your Dev tools, inspect your Network requests and Elements tab. See if GTM indeed is being fetched twice.
2. You don't need explicitly declared gtag if you use GTM.
3. The rest of the tags may be populated with GTM. you may want to use the request blocking feature to block GTM and see how many of the tags still remain in the DOM.
4. For further analytics debugging use Adswerve's plugin. You may as well consider Observe Point or a similar extension if the Network tab is too intimidating.