diff --git a/htdocs/install/repair.php b/htdocs/install/repair.php
index 4d3e28a38d3..b7f3f9eb5b6 100644
--- a/htdocs/install/repair.php
+++ b/htdocs/install/repair.php
@@ -78,6 +78,7 @@ print 'Option rebuild_product_thumbs (0 or \'test\' or \'confirmed\') is '.(GETP
 print 'Option force_disable_of_modules_not_found (0 or \'test\' or \'confirmed\') is '.(GETPOST('force_disable_of_modules_not_found','alpha')?GETPOST('force_disable_of_modules_not_found','alpha'):'0').'<br>'."\n";
 print 'Option clean_perm_table (0 or \'test\' or \'confirmed\') is '.(GETPOST('clean_perm_table','alpha')?GETPOST('clean_perm_table','alpha'):'0').'<br>'."\n";
 print 'Option force_utf8_on_tables, for mysql/mariadb only (0 or \'test\' or \'confirmed\') is '.(GETPOST('force_utf8_on_tables','alpha')?GETPOST('force_utf8_on_tables','alpha'):'0').'<br>'."\n";
+print 'Option repair_link_dispatch_lines_supplier_order_lines, (0 or \'test\' or \'confirmed\') is '.(GETPOST('repair_link_dispatch_lines_supplier_order_lines','alpha')?GETPOST('repair_link_dispatch_lines_supplier_order_lines','alpha'):'0').'<br>'."\n";
 print '<br>';
 
 print '<table cellspacing="0" cellpadding="1" border="0" width="100%">';
@@ -1122,6 +1123,130 @@ if ($ok && GETPOST('force_utf8_on_tables','alpha'))
     }
 }
 
+//
+if ($ok && GETPOST('repair_link_dispatch_lines_supplier_order_lines')) {
+    /*
+     * This script is meant to be run when upgrading from a dolibarr version < 3.8
+     * to a newer version.
+     *
+     * Version 3.8 introduces a new column in llx_commande_fournisseur_dispatch, which
+     * matches the dispatch to a specific supplier order line (so that if there are
+     * several with the same product, the user can specifically tell which products of
+     * which line were dispatched where).
+     *
+     * However when migrating, the new column has a default value of 0, which means that
+     * old supplier orders whose lines were dispatched using the old dolibarr version
+     * have unspecific dispatch lines, which are not taken into account by the new version,
+     * thus making the order look like it was never dispatched at all.
+     *
+     * This scripts sets this foreign key to the first matching supplier order line whose
+     * product (and supplier order of course) are the same as the dispatch’s.
+     *
+     * If the dispatched quantity is more than indicated on the order line (this happens if
+     * there are several order lines for the same product), it creates new dispatch lines
+     * pointing to the other order lines accordingly, until all the dispatched quantity is
+     * accounted for.
+     */
+    echo '<tr><th>Repair llx_commande_fournisseur_dispatch.fk_commandefourndet</th></tr>';
+    echo '<tr><td>Repair in progress. This may take a while.</td></tr>';
+
+    $sql_dispatch = 'SELECT * FROM ' . MAIN_DB_PREFIX . 'commande_fournisseur_dispatch WHERE COALESCE(fk_commandefourndet, 0) = 0';
+    $db->begin();
+    $resql_dispatch = $db->query($sql_dispatch);
+    $n_processed_rows = 0;
+    $errors = array();
+    if ($resql_dispatch) {
+        if ($db->num_rows($resql_dispatch) == 0) {
+            echo '<tr><td>Nothing to do.</td></tr>';
+            exit;
+        }
+        while ($obj_dispatch = $db->fetch_object($resql_dispatch)) {
+            $sql_line = 'SELECT line.rowid, line.qty FROM ' . MAIN_DB_PREFIX . 'commande_fournisseurdet AS line'
+                .       ' WHERE line.fk_commande = ' . $obj_dispatch->fk_commande
+                .       ' AND   line.fk_product  = ' . $obj_dispatch->fk_product;
+            $resql_line = $db->query($sql_line);
+
+            // s’il y a plusieurs lignes avec le même produit sur cette commande fournisseur,
+            // on divise la ligne de dispatch en autant de lignes qu’on en a sur la commande pour le produit
+            // et on met la quantité de la ligne dans la limite du "budget" indiqué par dispatch.qty
+
+            $remaining_qty = $obj_dispatch->qty;
+            $first_iteration = true;
+            if (!$resql_line) {
+                echo '<tr><td>Unable to find a matching supplier order line for dispatch #' . $obj_dispatch->rowid . '</td></tr>';
+                $errors[] = $sql_line;
+                $n_processed_rows++;
+                continue;
+            }
+            if ($db->num_rows($resql_line) == 0) continue;
+            while ($obj_line = $db->fetch_object($resql_line)) {
+                if (!$remaining_qty) break;
+                if (!$obj_line->rowid) {
+                    continue;
+                }
+                $qty_for_line = min($remaining_qty, $obj_line->qty);
+                if ($first_iteration) {
+                    $sql_attach = 'UPDATE ' . MAIN_DB_PREFIX . 'commande_fournisseur_dispatch'
+                        .        ' SET fk_commandefourndet = ' . $obj_line->rowid . ', qty = ' . $qty_for_line
+                        .        ' WHERE rowid = ' . $obj_dispatch->rowid;
+                    $first_iteration = false;
+                } else {
+                    $sql_attach_values = array(
+                        $obj_dispatch->fk_commande,
+                        $obj_dispatch->fk_product,
+                        $obj_line->rowid,
+                        $qty_for_line,
+                        $obj_dispatch->fk_entrepot,
+                        $obj_dispatch->fk_user,
+                        $obj_dispatch->datec ? '"' . $db->escape($obj_dispatch->datec) . '"' : 'NULL',
+                        $obj_dispatch->comment ? '"' . $db->escape($obj_dispatch->comment) . '"' : 'NULL',
+                        $obj_dispatch->status ?: 'NULL',
+                        $obj_dispatch->tms ? '"' . $db->escape($obj_dispatch->tms) . '"': 'NULL',
+                        $obj_dispatch->batch ?: 'NULL',
+                        $obj_dispatch->eatby ? '"' . $db->escape($obj_dispatch->eatby) . '"': 'NULL',
+                        $obj_dispatch->sellby ? '"' . $db->escape($obj_dispatch->sellby) . '"': 'NULL'
+                    );
+                    $sql_attach_values = join(', ', $sql_attach_values);
+
+                    $sql_attach = 'INSERT INTO ' . MAIN_DB_PREFIX . 'commande_fournisseur_dispatch'
+                        .         ' (fk_commande, fk_product, fk_commandefourndet, qty, fk_entrepot, fk_user, datec, comment, status, tms, batch, eatby, sellby)'
+                        .         ' VALUES (' . $sql_attach_values . ')';
+                }
+                $resql_attach = $db->query($sql_attach);
+                if ($resql_attach) {
+                    $remaining_qty -= $qty_for_line;
+                } else {
+                    $errors[] = $sql_attach;
+                }
+                $first_iteration = false;
+            }
+            $n_processed_rows++;
+
+            // report progress every 256th row
+            if (!($n_processed_rows & 0xff)) {
+                echo '<tr><td>Processed ' . $n_processed_rows . ' rows with ' . count($errors) . ' errors…' . "</td></tr>\n";
+                flush();
+                ob_flush();
+            }
+        }
+    } else {
+        echo '<tr><td>Unable to find any dispatch without an fk_commandefourndet.' . "</td></tr>\n";
+        echo $sql_dispatch . "\n";
+    }
+    echo '<tr><td>Fixed ' . $n_processed_rows . ' rows with ' . count($errors) . ' errors…' . "</td></tr>\n";
+    echo '<tr><td>DONE.' . "</td></tr>\n";
+
+    if (count($errors)) {
+        $db->rollback();
+        echo '<tr><td>The transaction was rolled back due to errors: nothing was changed by the script.</td></tr>';
+    } else {
+        $db->commit();
+    }
+    $db->close();
+
+    echo '<tr><td><h3>SQL queries with errors:</h3></tr></td>';
+    echo '<tr><td>' . join('</td></tr><tr><td>', $errors) . '</td></tr>';
+}
 
 print '</table>';