Hello, I used unsigned extension at Firefox ESR, according to the this page: https://support.mozilla.org/en-US/kb/add-on-signing-in-firefox I toggled the setting about signature to false. At the previous revision (I don't know the exact revision, but it might be this year), it works well and an unsigned extension was installed well. I updated the browser and re-installed the unsigned extension to update. To install the unsigned extension, i tried to drag-and-drop the .zip file (extension) at 'about:addon', but error occurs, saying "이 부가 기능은 손상된 것 같으므로 설치할 수 없습니다." (I think, this is translation of the following:"This add-on could not be installed because it appears to be corrupt.") So I added the unsigned extension through 'about:debugging#/runtime/this-firefox'. Then the unsigned extension is installed, but it is deleted when I close firefox. Could you let me know how to install the unsigned extension?