Steps to reproduce:

I open a webpage which contains many elements, to which there can be URI fragments in the page URL. (c.f. https://en.wikipedia.org/wiki/URI_fragment )
The http or https link, with which I open the webpage, contains one certain URI fragment.

The bug is difficult to reproduce. It doesn't happen each time.
But here I try to give steps:
Say you open https://en.wiktionary.org/wiki/browser#English Firefox scrolls to the Element "English" . This is a page with few elements. Now you click on the hyperlink of "-er". You now get to this page "https://en.wiktionary.org/wiki/-er#English:_agent_noun". This is a page with many elements. It is on pages with many elements that the problem sometimes occurs and sometimes not.

Actual results:

The browser opens the webpage and jumps to a much lower scrolling position than where the position of the element is, to which the URI fragment points.

Expected results:

The browser opens the webpage with the scrolling position jumping to where the element is, to which the URI fragment points.

Hi @user987643 on what Operating system are you seeing this issue ? I tried to reproduce this issue on a Windows 10 machine on Firefox Release 113, Beta 114 as well as our latest Nightly build but I cant seem to reproduce it, how often does it occur on your end ? Do you have any addons installed ? could you try it in safe mode ?
Here are some steps on how to start Firefox in Safe mode https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

You could also try our latest Nightly build and let us know if youre still seeing this issue there.
You can find the build here: https://nightly.mozilla.org/

(In reply to Rares Doghi, Desktop QA from comment #1)
I use the same operating system (Windows 10). I am afraid that I won't use the nightly build, because of the risk of data loss or data corruption, and other issues that could occur because of this unstable version of firefox.
Yes, I will try safe mode and check whether any addon could be the issue.
The main difficulty seems to be to reproduce the issue. I will report back when I have found a case that is more often than not reproducible.

I have found a page on which the bug occurs each time. It appears that the bug is connected with opening a page in a new tab.
https://en.wiktionary.org/wiki/multa
When I use the following step the bug occurs each time:
Click on "9 Italian" or "15 Spanish" in the list at the top of the page. The browser jumps to a much lower position than where the page element is.
Important: Use right-click "open link in new tab"
When I use the following step the bug doesn't occur at all:
Click on "5 Finnish" or "4 Esperanto". The browser jumps to the correct position of the element on the page.
Important: Use right-click "open link in new tab"

I tried it both with and without safe mode. The problem occurs in both modes.

Also: When I copy and paste the link into a new firefox tab it has the same behaviour as when I use right-click "open link in new tab".

Thanks for the extra steps @user987643 I was able to reproduce this issue in all versions of Firefox all the way back to 61. I will update the remaining flags. I did compare this to Chrome and it seems that Chrome will redirect the user correctly.