diff --git a/frontend/ui/data/onetime_migration.lua b/frontend/ui/data/onetime_migration.lua
index 82ea3ad4b..84fc9a144 100644
--- a/frontend/ui/data/onetime_migration.lua
+++ b/frontend/ui/data/onetime_migration.lua
@@ -12,7 +12,7 @@ local util = require("util")
 local _ = require("gettext")
 
 -- Date at which the last migration snippet was added
-local CURRENT_MIGRATION_DATE = 20250629
+local CURRENT_MIGRATION_DATE = 20250601
 
 -- Retrieve the date of the previous migration, if any
 local last_migration_date = G_reader_settings:readSetting("last_migration_date", 0)
@@ -888,28 +888,6 @@ if last_migration_date < 20250601 then
     SettingsMigration:migrateSettings(G_reader_settings)
 end
 
--- 20250629, Fix trailing slashes in wallabag directories #13987
--- https://github.com/koreader/koreader/issues/13987
-if last_migration_date < 20250629 then
-    logger.info("Performing one-time migration for 20250629")
-
-    local wb_lua = DataStorage:getSettingsDir() .. "/wallabag.lua"
-    if lfs.attributes(wb_lua, "mode") == "file" then
-        local wb_settings = LuaSettings:open(wb_lua)
-        wb_settings:readSetting("wallabag")
-
-        if wb_settings.data.wallabag.directory:sub(-1) == "/" then
-            wb_settings.data.wallabag.directory = wb_settings.data.wallabag.directory:gsub("/$", "")
-        end
-
-        if wb_settings.data.wallabag.archive_directory:sub(-1) == "/" then
-            wb_settings.data.wallabag.archive_directory = wb_settings.data.wallabag.archive_directory:gsub("/$", "")
-        end
-
-        wb_settings:saveSetting("wallabag", wb_settings.data.wallabag)
-        wb_settings:flush()
-    end
-end
 
 -- We're done, store the current migration date
 G_reader_settings:saveSetting("last_migration_date", CURRENT_MIGRATION_DATE)
diff --git a/plugins/wallabag.koplugin/main.lua b/plugins/wallabag.koplugin/main.lua
index 8e76be966..5a2758276 100644
--- a/plugins/wallabag.koplugin/main.lua
+++ b/plugins/wallabag.koplugin/main.lua
@@ -114,7 +114,7 @@ function Wallabag:init()
     self.archive_directory = self.wb_settings.data.wallabag.archive_directory
     if not self.archive_directory or self.archive_directory == "" then
         if self.directory and self.directory ~= "" then
-            self.archive_directory = self.directory.."/archive"
+            self.archive_directory = FFIUtil.joinPath(self.directory, "archive")
         end
     end
 
@@ -757,7 +757,7 @@ function Wallabag:downloadArticle(article)
         end
     end
 
-    local local_path = self.directory.."/"..article_id_prefix..article.id..article_id_postfix..title..file_ext
+    local local_path = FFIUtil.joinPath(self.directory, article_id_prefix..article.id..article_id_postfix..title..file_ext)
     logger.dbg("Wallabag:downloadArticle: downloading", article.id, "to", local_path)
 
     local attr = lfs.attributes(local_path)
@@ -1079,7 +1079,7 @@ function Wallabag:processRemoteDeletes(remote_ids)
     local count = 0
 
     for entry in lfs.dir(self.directory) do
-        local entry_path = self.directory.."/"..entry
+        local entry_path = FFIUtil.joinPath(self.directory, entry)
 
         if entry ~= "." and entry ~= ".." and lfs.attributes(entry_path, "mode") == "file" then
             local local_id = self:getArticleID(entry_path)
@@ -1128,7 +1128,7 @@ function Wallabag:uploadStatuses(quiet)
             local skip = false
 
             if entry ~= "." and entry ~= ".." then
-                local entry_path = self.directory.."/"..entry
+                local entry_path = FFIUtil.joinPath(self.directory, entry)
 
                 if DocSettings:hasSidecarFile(entry_path) then
                     logger.dbg("Wallabag:uploadStatuses:", entry_path, "has sidecar file")
@@ -1324,7 +1324,7 @@ function Wallabag:archiveLocalArticle(path)
 
     if lfs.attributes(path, "mode") == "file" then
         local _, file = util.splitFilePathName(path)
-        local new_path = self.archive_directory.."/"..file
+        local new_path = FFIUtil.joinPath(self.archive_directory, file)
         if FileManager:moveFile(path, new_path) then
             result = 1
         end