Update: Thunderbird 38.0.1 released

[HansV]

Thunderbird 38.0.1 was released on the 11th of June, 2015. f you already have Thunderbird, use the internal update mechanism; otherwise, you can download it from Download Thunderbird in your language.

(Remark: Thunderbird 38.0 was never publicly released)

Changes: see the Release notes

[viking33]

Unfortunately, TB 38.0.1 does not yet support one on my add-ons. ( Extra Folder Columns ) Apparently, later versions of TB do not allow the modifications of the .rdf files, that would patch the older versions to the later ones.
I'd rather wait for the author of the add-on to release an update, hopefully!