Steps to replicate the issue:

• Go to https://bn.m.wiktionary.org/wiki/%E0%A6%AC%E0%A6%BE%E0%A6%B2%E0%A6%BE%E0%A6%AE
• Click the edit icon beside "বাংলা"

What happens?:
The section is collapsed instead of opening the editor.

What should have happened instead?:

The editor should have been opened.

Other information:
This only seems to be affecting sections that are generated with the use of templates that have titles starting (and ending) with a hyphen, in this specific case -bn-.