Typo on paragraph jlegewie#10

jlegewie#10: `Firfox` > `Firefox`

Author: kant

readme.md

@@ -7,7 +7,7 @@ Detailed information are available from the [zotfile website](http://www.zotfile
 
 ## Installation
 
-For *Zotero 5*, first download the extension file (follow the download link above, click on the .xpi file for the most recent release). Now start Zotero 5 and go to "Tool -> Add-ons -> Tools for all Add-ons (the small, drop-down wheel in the top right corner) -> Install Add-on From File" and select the downloaded .xpi file. For *Zotero 4.x*, the process is different for Zotero for Firfox and Zotero Standalone. For Zotero 4.x Firefox, go to the [Mozilla Add-Ons page](https://addons.mozilla.org/en-us/firefox/addon/zotfile/) and follow the instructions. For Zotero 4.x Standalone, use the same steps as for Zotero 5 but download the .xpi file from [here](https://addons.mozilla.org/firefox/downloads/file/585224/zotfile-4.2.8-fx.xpi?src=dp-btn-primary)
+For *Zotero 5*, first download the extension file (follow the download link above, click on the .xpi file for the most recent release). Now start Zotero 5 and go to "Tool -> Add-ons -> Tools for all Add-ons (the small, drop-down wheel in the top right corner) -> Install Add-on From File" and select the downloaded .xpi file. For *Zotero 4.x*, the process is different for Zotero for Firefox and Zotero Standalone. For Zotero 4.x Firefox, go to the [Mozilla Add-Ons page](https://addons.mozilla.org/en-us/firefox/addon/zotfile/) and follow the instructions. For Zotero 4.x Standalone, use the same steps as for Zotero 5 but download the .xpi file from [here](https://addons.mozilla.org/firefox/downloads/file/585224/zotfile-4.2.8-fx.xpi?src=dp-btn-primary)
 
 To install the **development version** on github: