From an a11y perspective it is bad to open a new window/tab. That removes
the ability for someone using assistive technology to use the back button
to return to where they are.

In addition while it is possible to force a link to open in a new
window/tab using the ctrl key it is not possible to force a link to open in
the same window/tab

from accessibility perspective is not always bad to open in new window.

when you exchange app sessions you should, especcially if one is secure and the other not, IMHO, open in new tab/window.

Use of the target attribute provides an unambiguously machine-readable indication that a new window will open.
User agents can inform the user, and can also be configured not to open the new window.
For those not using assistive technology, the indication would also be available from the link text.

Example: <a href="help.html" target="_blank">Show Help (opens new window)</a>

https://www.w3.org/TR/2016/NOTE-WCAG20-TECHS-20160317/H83

Also

The objective of this technique is to limit the use of links or buttons that open new windows or tabs within Web content. In general, it is better not to open new windows and tabs since they can be disorienting for people, especially people who have difficulty perceiving visual content. However there are some situations where it is preferable from an accessibility perspective to open a new window or tab.
[...]
Example 2: Secure Web site
A page on a secure Web site includes a link to an external page that is outside of the secure session. The link opens in a new window or tab since opening the link in the same window will break or destroy the secure session.

Source: https://www.w3.org/TR/WCAG20-TECHS/G200.html

Thank you both for sharing your views, I was suggesting "new Tab" to distinguish back/front-end similar than the "site preview" that is a front-end view only.

• I'm trying to educate my users to never use the back button while in the back-end (as this is creating locks on items "core and 3rd party" that can be removed only by the locks creators or by the Global Check-in access rights), this view looks like an exception across the Joomla console.

What about modal?

Extending the issue:

• BE > Components > Search > Show Search Results.
• Enter a search word in search filter. Click search button.
• Click Results label > landing in FE.
• Click back button of browser. The browser will block BE with a "Document Expired" page.
• You need 2 additional clicks ("Try again" + "Resend") to come back to BE.

Another find: I tested with a Search Phrase that had 1 Hits. After any click on Results label Hits is increased by 1.

.

I would expect the hits to increase as clicking on the link is doing a new search

Closed as we have a PR for testing see #12626