Seen this bar before, Either a crippled form or 3rd party? does not seem the standard wysiwig provided with e107.
Could also indicate that some css is not called (cdn) Using different admin thems would only lead to position change, not missing items.
Even other editors (non e107) would provide centering. The question arises why Formats (H1,2 etc) are displayed while they normally would occupy a dropdown.
this is the standard editor (with or without tiny installed and active)
and below the normally active wysiwig.
see the differences? So an answer is presently not possible.. (ps tinymce=editor) has had the last 3 months no changes and still looks the same as before that timeframe.
Edit : since you are trying to use (other post) tabby ui; influence??