Server License: All updates have the release date set to 2026-10-02. Your ESS should be the same or higher to be able to update your server. This release is available to all countries except for Japan.
π¦ New ISL Light / ISL AlwaysOn Programs
This release ships ISL Light / ISL AlwaysOn 5.0.2551.192, which includes all new features, improvements and bug fixes from the previous cloud releases 5.0.2551.150, .156, .176 and .184.
- ISL Light 5.0.2551.192
- ISL AlwaysOn 5.0.2551.192
- ISL Light 5.0.2551.184
- ISL AlwaysOn 5.0.2551.184
- ISL Light 5.0.2551.176
- ISL AlwaysOn 5.0.2551.176
- ISL Light 5.0.2551.156
- ISL AlwaysOn 5.0.2551.156
- ISL Light 5.0.2551.150
- ISL AlwaysOn 5.0.2551.150
π New Features
Launch installed ISL Light when joining a session
On the Join a Session page and the Join as Operator invite page, if ISL Light is already installed on your machine, it now launches directly instead of making you download a fresh installer each time. On the join page, the launch is attempted as soon as a valid session code is typed or pasted, and the page shows an “Operator is waiting for you” view with Download, Connect in Browser (where allowed), and a “Launch application” button to retry the launch. If nothing picks up the link within a couple of seconds, a “Couldn’t open the application. Please download and install it below.” hint appears above the Download button.
The URL scheme used for the launch can be overridden per customization with the “ISL Light installation schema” field in the customization settings. It sets a custom scheme name (for example, acmesupport) so that joiners of that customization launch the branded client instead of stock ISL Light. Values are normalized to lowercase ASCII letters and must be 5-16 characters long. Invalid entries fall back to isllight and are logged.
- Automatic session code detection on the join page: as soon as someone enters a valid session code, the page recognizes it and moves straight to the next screen. There is no need to press Join first.
- Running the installed app: if ISL Light is already installed, the user gets a browser prompt to open it. If they tick “Always allow”, future sessions skip the prompt entirely; entering the code or opening the link is enough. No extra clicks and no waiting on a download they don’t need.
- Same behavior on invite links: opening an invite link also triggers the prompt or launches the installed app automatically.
- Download flow for new users: if ISL Light isn’t installed, automatic session code detection still moves to the next page and shows a Download button. Once clicked, the user gets confirmation that the download has started and a prompt to run the installer.
- Retry button: on the join screen, a “Launch application” button lets the user try opening the app again without reloading the page, which is useful if they missed the initial prompt.
- Custom branding for enterprise customers: admins can configure their own app name and branding so that the customer’s branded client opens instead of the default ISL Light.

islonline.net (Join a Session) > Running the installed app
βStay logged inβ (persistent login)
Support for end-to-end persistent login for browsers and supported native applications was added to ISL Conference Proxy.
ISL Light now supports persistent login on the server side, so users stay logged in between application launches. Instead of a password, a rotating one-time token is stored on the device and changes on every login. Reusing an old, already-rotated token is treated as theft and revokes that login chain. The chain is also tied to the country it was created from, so logging in from a different country revokes it and requires a full login again. It is automatically revoked on a password reset, email change, account disable, or any 2FA change, and it can also be revoked remotely by an admin at any time.
New settings were added to /conf > Security > Authentication:
- Allow “Stay logged in”: controls whether users can remain logged in across application restarts. When disabled, “Stay logged in” ends immediately for everyone, including users who already had it active, and all users must log in again. (default: Yes)
- Allow “Stay logged in” for SSO and external users: controls whether users authenticated through Single Sign-On (SSO) or an external identity provider (such as LDAP) can use “Stay logged in”. (default: Disabled)
- Disabled: after the current session expires, the user must log in through the identity provider again.
- Limited to idle lifetime: “Stay logged in” remains available only for the configured idle lifetime, measured from when it was originally issued. Using “Stay logged in” does not extend this deadline.
- Enabled: each successful use of “Stay logged in” renews the idle lifetime, up to the configured maximum duration.
- Important: when this setting is enabled, disabling or deleting a user in an external identity provider does not immediately revoke existing “Stay logged in” sessions. To prevent further access, also disable or delete the user in the web portal.
- “Stay logged in” idle lifetime (1w 2d 3h 4m 5s): defines how long a user can remain inactive before “Stay logged in” expires. Each time the user returns, the idle timer is reset. If the user does not return before the idle lifetime expires, they must log in again with their credentials. (default: 2w)
- “Stay logged in” maximum duration (1w 2d 3h 4m 5s): defines the maximum amount of time “Stay logged in” can keep a user logged in, measured from when it is first used. Returning to the application resets the idle timer but does not extend this maximum duration. Once the limit is reached, the user must log in again with their credentials. (default: 365d)

Webportal > Administration > Settings > Security > Login
Native support for Apple Silicon (arm64)
ISL Conference Proxy can now distinguish Apple Silicon Macs from Intel Macs when serving downloads, actions, and plugins. Programs can be published with an “arch” tag listing one or more architectures (for example, arm64;x86_64 for a universal build, or a single value for an architecture-specific build), and clients receive the native build matching their machine whenever one is available. When no native arm64 build is published for an Apple Silicon Mac, the matching x86_64 build is offered instead. Native builds always take precedence over this fallback.
Customizations dashboard
Domain administrators can now manage ISL Light customizations from a new dashboard in the Administration module, available at /users/customization. From the list view, you can create, duplicate, reset, and delete customizations, and mark one as the default for the domain. Each customization is scoped to a single domain, and only one can be the default at a time. Marking a new one as default automatically clears the flag on the previous one.
Each customization covers branding (name, logo, icon, key visual, and primary, secondary, and button text colors) and a set of ISL Light session options, including login behavior (“Forgot password”, “Remember me”), visible tabs (“Join a session”, “Sessions” tab, “Computers” tab), stream quality, black screen with a configurable timeout, automatic recording, locking the computer on session start, end, or connection loss, transport options, and URLs to open on session start and end. Uploaded images must be PNG or JPG and no larger than 2 MiB.

Web Portal > Customization > Logo & Colors
Two new permissions were added:
- Manage customizations (domain admin only): grants access to the Customization dashboard, where domain customizations can be viewed, created, updated, and removed. Customizations can be applied to the entire domain or to selected users. Disabling this setting removes access to the Customization dashboard. Please note that the user must already have the Domain Admin role to use this feature (see the “Domain Admin” setting).
- Enable domain customizations (server administrator only): controls whether domain customizations are available for this domain. When enabled, Domain Admins can access the Customization dashboard (if they have the appropriate permissions). When disabled, the Customization dashboard and all related settings are unavailable for this domain, regardless of Domain Admin permissions.
The Customization dashboard is available in web version v2500 and later.

Web Portal > Customization > Configuration
Configuration: control ISL Light’s behavior using the same options you would otherwise set with command-line arguments, organized into:
- Session: automatic recording, black screen (curtain mode) and its timeout, the client top bar, opening a URL on session start or end, desktop background visibility during streaming, behavior on session start, stream quality, and automatically starting audio or video calls.
- Dashboard: showing the Computers and Sessions tabs, inviting another operator, the “Remember password” checkbox, and transferring a session to another operator.
- Login: the Forgot Password link, the Join a Session option, and the “Remember me” checkbox.
- Security: locking the remote computer on connection loss, on session end, or at session start.
- Network: transport options for the session.
Customization JWT events
ISL Conference Proxy now sends JWT webhook events when customizations are created, updated, or deleted, in addition to the existing user and domain events. This applies to changes made through both the server administration pages and the web API, so external systems can track the full lifecycle of a customization.
Three new toggles are available under Integration > JWT webhook hooks:
- Customization Create: fires when a new customization is added (whether created manually or uploaded as a zip).
- Customization Update: fires when an existing customization is modified and includes the changed fields in the payload.
- Customization Delete: fires when a customization is removed.
Each toggle can be enabled independently, and all three are off by default.
Customization export (Integrator)
Integrators can now export a customization as a zip file through the new API call integrator/system/customization/export/1. The call takes the customization UUID and returns a download URL that remains valid for 5 minutes.
To use this call, the JWT key must have both the existing system_integrator right and the new customization_export right, which grants permission to export customizations.
Action on customization domain or integrator_key mismatch
A new setting, “Customization ownership enforcement”, was added to /conf > Security. It determines the enforcement behavior when a client attempts to start or join a session using a customization that originates from a different domain or was created by a non-matching integrator:
- None (default): silently allows the mismatch.
- Report: logs the mismatch.
- Block: rejects the session outright.
Delete computers from Administration
Domain administrators can now delete computers directly from the Administration module. The “Delete Computer” action is available as a primary button on the computer details page and as a custom action in the computer list sidebar, and it shows a confirmation dialog before the computer is removed.
The action requires both domain administrator and computer editing permissions. Users without the required permissions will see the action disabled, with a tooltip explaining why. Each deletion is recorded in the audit log along with the computer description and its previous owner.

Web Portal > Administration > Computers > Side Panel (Delete Computer)
Delete user from Administration
Administrators can now delete users directly from the Administration module, with safeguards against accidental data loss. The delete action is blocked for your own account and for the main account owner, and it is also blocked if the user owns any computers or computer groups.
When deletion is blocked due to owned resources, the confirmation dialog shows “Manage Computers” and “Manage Computer Groups” links. These open the corresponding tabs with an owner filter already applied to the user being deleted, so you can reassign or remove those items and then retry the deletion. The Delete User button is available in web version v2500 and later.

Web Portal > Administration > Users > Side Panel (Delete User)
When deleting a user from the Administration interface, domain admins can now see a list of associated data that will be removed along with the account, grouped by category with counts. Only categories that have associated data tracking enabled for users, and are configured to be deleted with the user, are included in the list. By default, this is limited mainly to the user account itself.
π§ Improvements
Split Session Code
Session and grant codes are now displayed as groups of three digits separated by spaces (for example, 12345678 appears as 123 456 78). This affects the join portal input field, the Sessions list and session details in ISL Light, the Add Remote Computer dialog and session details in ISL AlwaysOn, and the Code columns in ISL Light, ISL Groop, and ISL Meetings reports.
In the join portal, the input field reformats the code as you type or paste, accepting raw, spaced, hyphenated, or full-width-digit codes and normalizing them. When a code is submitted or copied via Copy Code or Copy Session Code, the raw digits are used without spaces, so pasting a copied code into other systems works without manual cleanup. CSV and XLS report exports also contain the raw digits.

Web portal (islonline.net)> Join a Session (Split session code)
Reworked File Storage UI
The File Storage pages in Server Administration have been reworked. The per-server “Ver. on N” columns are replaced by a single “Server status” column that shows a short summary (present, old, and missing counts). Clicking a cell opens a popup listing the server IDs grouped by file version, with a separate “Missing on:” section when applicable. Both the local and remote file tables now support a substring file name filter and pagination (50 per page by default, with 25, 50, 100, and 500 options).
On module pages, files in the remote table are now selectable through a new “Select” column, and per-server deletion has moved into a “Delete from servers” picker below the table, matching the existing “Copy to servers” control: tick the files, tick the target servers, and click “Delete selected” to remove the files from only those servers.
Web pages v2600
Web pages v2500 were copied into the new version v2600, which is now the default version.
π Security
Upgrade OpenSSL to 3.5.9
OpenSSL was updated to 3.5.9.
Upgrade Go to version 1.26.7
Go was upgraded to 1.26.7.
π Bug Fixes
Use a backward-compatible query in older web APIs
In previous versions, loading the user list in the administration pages failed with an “Unexpected internal error” on servers that did not have the core login module installed. This was redesigned so that older page versions again use a user listing query that does not depend on the core login module. The issue should no longer be reproducible.
License usage start-of-hour slot flush task can cause a deadlock
In previous versions, starting an ISL Light session could cause the server to crash due to a watchdog timeout. This was redesigned so that license usage processing no longer conflicts with new session starts. The issue should no longer be reproducible.
Decode elevation session on redirected server
In previous versions, performing a session elevation (such as confirming your password to access two-step verification settings) could fail with an “Unhandled exception in WEBAPI2 call” error when the request was handled by a different server in the grid than the one holding your session. This was redesigned so that the elevation step now correctly loads the session on whichever server processes the request, and invalid sessions return a proper login error instead of an unhandled exception. The issue should no longer be reproducible.
Set and use hrsv hint when making webapi calls
In previous versions, in multi-server setups, a web API call could be handled by a different server than the one that served the page, which in some cases caused the request to fail or behave incorrectly. This was redesigned so that web API calls are now directed to the same server that served the originating page. The issue should no longer be reproducible.
User password set from “Administration” tab does not accept characters that are accepted under “Users” tab
In previous versions, setting a user password from the Administration tab rejected certain characters that were accepted when setting the same password from the Users tab. This was redesigned so that password validation now behaves the same way in both places, including checks for password strength and recently used passwords. The issue should no longer be reproducible.
SSL: fix parsing of HMAC keys in EAB
In previous versions, installing a certificate with an EAB key in unpadded format failed with the error “Failed to decode EAB key.”. This was redesigned, and both padded and unpadded EAB keys are now accepted. The issue should no longer be reproducible.
ISL Meetings: improved error message when granting control fails during screen sharing
When sharing a single window in a meeting and attempting to give or grant remote control, the error dialog now explains the actual problem. The title reads “Remote control is not available for window sharing”, and the message instructs the user to stop sharing and share the entire screen instead of a specific window.
Previously, these attempts failed with the generic “Error occurred. Please contact your system administrator.” dialog, which gave no indication of what to do next. Sharing the entire screen and granting control works as before.
ISL Meetings: Audio/Video settings are cut off and scrollable to the right
In previous versions, when opening the Audio/Video section of the meeting settings in Chrome or Edge, the microphone and camera options appeared side by side and were cut off, requiring horizontal scrolling to see all controls. This was redesigned so that the Audio/Video settings now fit within the settings pane and stack vertically when there is not enough room, regardless of the names of the detected devices. The issue should no longer be reproducible.
ISL Meetings: audio feedback loop when Stream Remote Sound is enabled
In previous versions, sharing your screen with the “Also share system audio” option enabled caused a local audio feedback loop, where the shared audio was captured again and played back repeatedly. This was redesigned so that the local preview of your own shared screen no longer plays its audio back through your system. The issue should no longer be reproducible.
ISL Meetings: software policy and version support
In previous versions, administrators could not have the default meeting application vary by region without manually configuring each user or site. This was redesigned so that, when no explicit default has been chosen, the default meeting application can now be determined by the software release policy, while any explicit administrator or user choice still takes precedence. The issue should no longer be reproducible.










