The CodeMirror extention In Russian Wikisource break the edit field of pages.
This enabled by button "syntax highlighting" of new edit toolbar. (The new edit panel globally replaced the previous one about 1-2 months ago, as I remember. There were no notes about it. Therefore, it was very shocking, after accidentally pressing a button, to encounter massive errors on all pages of the Wikisource. I think this extension should be packed as a gadget or beta-feature, like all similar ones.)
In namespace Page the edit field of proofreading pages is broken.
To example, this normal page.
After 1st pressing of the button the size of fonts are reduced to about half. In console has red error.
After 2nd pressingoff/on the size of fonts are restoring. On button appears borders as 'pressed' (1st pressed was not-pressed?).
If open a edit page after button is pressed. (open to edit, enable the button, close, open to edit.)
Then the edit field moved to top, and broken the layout of fields of scan image and colontituls.
After several clicks on button appears additional the normal edit field below. But above remains large edit fields.
Disabling work other gadgets. As I understand, it because gadgets works with the edit field in certain div in html. But this extention creating other edit field and show it in browser.
There is the gadget 'deyatifikator' that hard important for Russian Wikisource. RuWS specific is that almost all texts there are published before 1917 year, they in old orphography. So, necessery normal work of the gadget for convert texts to modern orphograhy.
Also, necessary work of other gadgets, e.g. Wikificator.
Broken syntax highlighting
To example, in Main namespace a page https://ru.wikisource.org/w/index.php?title=%D0%A0%D0%A1%D0%9A%D0%94/Graecia&action=edit
There the text is no more than two pages in size, but dont work syntax highlighting.
What about normal for Wikisource pages with size 0.5Mb, and to 1.5Mb?
All highlighting disappeared. Just opened edit page, scroll to bottom (highlighting here work only for 1st half page), placed one any letter in text bottom. Scroll to up. - And no any highlighting.
The extension page says that it have no conflict with gadget "SyntaxHighlighter" (from user settings, on bottom list of Edit section). But if enable it, then begin other bugs.
Compressed edit field, no way to expand it.
Appears if enable in user settings this gadget, open a page to edit, then again press the tab "Edit" (rus. "Править"), and press the button on/off. This glitch is not stable.
There are other glitch , they not stable. (Or maybe fixed yesteday, I dont now, the extention seems as a beta under developing.)
Perhaps, because conflict with mentioned gadget. So the edit page loading very long or freezes. And the browser tab overload 100% of CPU and make leaking memory.
All edit text shows as underlined and strange colored.
Or all text colored strange blue color, if change only one letter of any word then color of all text changing, if after change other letter then all text color changed again to other color, and so on.
In other time, a page to edit there is no syntax highlighting, or only template on top edit text is colored.
Perhaps it is better to move this to a gadget, so that those who wish can have the ability to enable/disable?
Many user can't work with such color theme, or be beta-testers. Also, it is big problem for wiki-enginers, to each time, when users report about any wiki bugs of templates or gadgets, wasting time checking for whether this is a error of the extention or something other.
Reproduce and settings:
This bugs starts If just enable this button of edit toolbar. Have on all edit pages of ru-Wikisource. User settings are by defaults, all betafeatures disabled, user scripts disabled. Theme is Monobook or Vector. The bug have in Chrome/Chromium and Firefox.
Did not any changes scripts or Meta settings in our ru-Wikisource. I found this problem yesterday.
Appears if login to Wikisource, but not edititng as anonim. Perhaps this problem no in other interwikies, e.g. I did not found it in Suomi Wikisource, however no any gadgets there.
The topic on ru-forum, where the presence of glitches also confirmed by the bureaucrat.