Failed to look up view X on reloading

[Moritz Friedrich]

I noticed that whenever I reload nodebb, I get error messages like this one in the log:

31/7 23:47 [12036] - error:  Error: Failed to lookup view "500" in views directory "/var/www/node/nodebb/public/templates"
    at EventEmitter.render (/var/www/node/nodebb/node_modules/express/lib/application.js:579:17)
    at ServerResponse.render (/var/www/node/nodebb/node_modules/express/lib/response.js:961:7)
    at ServerResponse.res.render (/var/www/node/nodebb/src/middleware/middleware.js:337:10)
    at /var/www/node/nodebb/src/routes/index.js:223:9
    at /var/www/node/nodebb/src/middleware/middleware.js:192:12
    at /var/www/node/nodebb/node_modules/async/lib/async.js:589:17
    at done (/var/www/node/nodebb/node_modules/async/lib/async.js:126:15)
    at /var/www/node/nodebb/node_modules/async/lib/async.js:32:16
    at /var/www/node/nodebb/node_modules/async/lib/async.js:586:21
    at /var/www/node/nodebb/node_modules/templates.js/lib/templates.js:160:12
Error: Failed to lookup view "500" in views directory "/var/www/node/nodebb/public/templates"
    at EventEmitter.render (/var/www/node/nodebb/node_modules/express/lib/application.js:579:17)
    at ServerResponse.render (/var/www/node/nodebb/node_modules/express/lib/response.js:961:7)
    at ServerResponse.res.render (/var/www/node/nodebb/src/middleware/middleware.js:337:10)
    at /var/www/node/nodebb/src/routes/index.js:223:9
    at /var/www/node/nodebb/src/middleware/middleware.js:192:12
    at /var/www/node/nodebb/node_modules/async/lib/async.js:589:17
    at done (/var/www/node/nodebb/node_modules/async/lib/async.js:126:15)
    at /var/www/node/nodebb/node_modules/async/lib/async.js:32:16
    at /var/www/node/nodebb/node_modules/async/lib/async.js:586:21
    at /var/www/node/nodebb/node_modules/templates.js/lib/templates.js:160:12

I think it is users trying to access the page while reloading, but it made me wonder if there is a way to prevent this from happening? Also, I have currently three worker threads enabled. Shouldn't they be restarted successively so every request can be handled?