1Password tag rendering bug?

The "Tags tree" on macOS and in webbrowser (= 1Password website, both in Safari and Firefox) is rendered differently than on iOS and iPadOS. The version of 1Password for macOS in question is 8.12.10 (81210036). However, I saw this rendering issue in previous versions as well. I don't know when it started though, but I am sure the rendering was the same across macOS and iOS/iPadOS some time ago.

I use nested tags: "IT-systemen" and "IT-systemen/SSH keys" for example. In iOS this is rendered in the Tags tree as:

However, in 1Password on macOS (and on the website) this is rendered as:

As shown, the tag "IT-systemen/SSH keys" is rendered under the "IT-systemen - anderen" tag and not the "IT-systemen" tag.

Questions:

• Is this a bug?
• Am I using tags or nested tags in the wrong way?