When I view the Apps screen in Odoo 12, there often (not always) is an "Uncaught TypeError" popping up:

Fehler:
Uncaught TypeError: this.$buttons.off(...).destroy is not a function
https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:2682
Zurückverfolgung
TypeError: this.$buttons.off(...).destroy is not a function
    at Class.destroy (https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:2682:343)
    at Class.prototype.<computed> [as destroy] (https://[site.name.here]/web/content/1914-f723579/web.assets_common.js:3538:488)
    at Class._removeAction [as _super] (https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:484:334)
    at Class._removeAction (https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:508:310)
    at Class._removeAction (https://[site.name.here]/web/content/1914-f723579/web.assets_common.js:3541:371)
    at Function._.each._.forEach (https://[site.name.here]/web/content/1914-f723579/web.assets_common.js:12:558)
    at Class._removeControllers (https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:484:518)
    at Class._pushController (https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:482:6)
    at https://[site.name.here]/web/content/1929-40cb097/web.assets_backend.js:465:6
    at https://[site.name.here]/web/content/1914-f723579/web.assets_common.js:802:681

(Just to state the obvious: I replaced the site address with [site.name.here])

The problem appeared somewhere along the process of installing various apps and modules, but I didn't notice exactly when.
I also have no idea where to find the /content/… data mentioned here.