I am trying to create lot number using stock.view_production_lot_form, but after selecting a product and clicking the save button I get the error which is pasted at the bottom of this post.

If I remove the product_qty field from the form view above the error does not appear and I can save the record. (product_qty on the module stock_production_lot is a computed field, based on the quantity field of related stock.quant ... when creating a lot from scratch as opposed to via a picking there are no related quants and so product_qty should be submitted as 0.0)

Besides the database above, which I will call database A, three other databases on the same server can be used as points of comparison. When I look at the relevant tables, models and views in phppgadmin, Settings/General Settings/Technical/Models and Settings/General Settings/User Interface/Views, the databases below seem identical to me.

Database B  is a new database with only the stock module installed and with lot/serial with expiration date enabled in the inventory settings. The error does not appear on Database B.

Database C shares the configuration and customizations of A, but they were developed in parallel. I thought the two were identical. But the error does not appear on database C.

Database D is a duplicate of A with the customizations to stock.production.lot and associated views rolled back (all customizations were minor: I had made name and life_date required, renaming Lot/Serial form, menuitems and action to Lots). The error appears on database D.

Please help me identify the source of the error.

Thanks

*****

Error:
TypeError: this.$input is undefined

https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:2622
Traceback:
_compute_result@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:2622:74
commitChanges@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:2617:509
commitChanges/defs<@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:1322:184
_.collect@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:13:270
commitChanges@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:1322:123
exec/<@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:4010:295
then/</</<@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:802:678
fire@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:796:281
add@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:797:467
then/</<@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:802:631
each@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:625:758
then/<@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:802:553
Deferred@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:803:189
then@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:802:518
exec@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:4010:257
saveRecord@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:1310:787
saveRecord@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:1408:354
OdooClass.extend/</prototype[name]</<@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:3816:485
_onSave@https://www.website.com/web/content/617-eb44ca6/web.assets_backend.js:1416:801
dispatch@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:892:378
add/elemData.handle@https://www.website.com/web/content/606-6f5b62b/web.assets_common.js:865:151