I have updated/upgraded all the phpBB3 extensions and language packs. Took awhile, need to always pay attention to the details.
Please report any craziness encountered. 
Update: The Japanese and Hebrew language packs are not fully complete for the latest version of phpBB and are missing text for some variables. Though they are close enough for now. Not many users appear to use these 2 languages at this time so it will not be a significant impact on performance.
@rockedge Don't know if this is related but I noticed that the selection popup for creating mention code has become unreadable.
Is the old [mention] tag still usable and what's behind the new [smention] tag and what is the function of the the u=<number>?
@MochiMoppel I have not forgotten!!! If you remember, we went through this adjustment of the CSS color values when we first incorporated the simple mention extension.
As I remember you are using the ne-blackgreen theme style and I have been able to see the same problem. I will look at the prevoius version to see what values we used then and perhaps even improve the configuration.
We were using the older version of simple mention that used the BBCode [mention][/mention] and now it is [smention u=xxxx][/smention] with the u=xxxx being the actual position number in the registered user list that the mentioned user has.
The extension is backwards compatible with the BBCode [mention][/mention] but only on existing posts. All new or edited posts will need to use the newer BBCode [smention u=xxxx][/smention].
Also this form will work correctly : [smention][/smention].
So no fear MochiMoppel with your help we'll dial in a better color combination
@MochiMoppel Fixed it I hope. Please test it on the style you are using.
@rockedge No, I don't remember. Are you sure it was me? The mention feature always worked for me ... until a few days ago.
It now works again. Thanks for fixing.