Ok I tried to change that “Plupload language code” setting directly on database, I found the table wp_sfoptions where a there is a field option_name that have the value as follow:
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a:20:{s:12:”showinserted”;b:1;s:9:”thumbsize”;s:2:”80″;s:10:”imgquality”;s:3:”100″;s:12:”thumbquality”;s:3:”100″;s:10:”imagetypes”;s:19:”jpg, jpeg, gif, png”;s:11:”imageinsert”;b:1;s:12:”imagemaxsize”;s:5:”51200″;s:13:”imagemaxwidth”;s:1:”0″;s:14:”imagemaxheight”;s:1:”0″;s:11:”mediainsert”;b:0;s:10:”mediatypes”;s:80:”dcr, mov, qt, mpg, mp3, mp4, mpeg, avi, wmv, wm, asf, asx, wmx, wvx, rm, ra, ram”;s:12:”mediamaxsize”;s:1:”0″;s:10:”mediawidth”;s:3:”320″;s:11:”mediaheight”;s:3:”240″;s:9:”filetypes”;s:18:”txt, rtf, doc, pdf”;s:11:”filemaxsize”;s:5:”51200″;s:10:”prohibited”;s:106:”php, php3, php5, js, html, htm, phtml, asp, aspx, ascx, jsp, cfm, cfc, pl, bat, exe, dll, reg, cgi, sh, py”;s:12:”useforphotos”;b:0;s:4:”lang”;s:2:”en“;s:9:”dbversion”;i:1;}
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I changed the value (in red) to “fr”. Now the setting in “Plupload language code” is “fr” and remains like that.
But unfortunately, that change had no impact and I’m still unable to get the “file uploader” showing up when the translation plugin is active.