The buttons in edit mode of proofread has gone starting from the deployment.
Not Release-Engineering-Team - see T175304: Page status buttons do not appear any more in Wikisource
@Aklapper I think we probably need to revert to wmf.16 (at least wikisource wikis)
@Ladsgroup: This task is closed as a dup. Feel free to comment on T175304 instead :)